Deploying Node.js application with Azure DevOps results in an error about a missing module

I'm trying to deploy my Angular project with Azure DevOps. The build and deploy fase seem to go correctly judging by the green checkmarks for every stage. When I try to visit the webpage it shows the application error page with a link to the diagnostic resources.

The project is located on GitHub, during the build it gets pulled from there. Eventually after all tasks have been completed the app isn't launched and I get the following error in the diagnostic resources:

2019-10-04T11:19:47.004554842Z A P P   S E R V I C E   O N   L I N U X
2019-10-04T11:19:47.004559742Z 
2019-10-04T11:19:47.004564342Z Documentation: http://aka.ms/webapp-linux
2019-10-04T11:19:47.004569042Z NodeJS quickstart: https://aka.ms/node-qs
2019-10-04T11:19:47.004573843Z NodeJS Version : v10.10.0
2019-10-04T11:19:47.004578543Z 
2019-10-04T11:19:47.065230218Z /opt/startup/init_container.sh: line 32: [: ==: unary operator expected
2019-10-04T11:19:47.108722107Z Oryx Version : 0.2.20190730.1, Commit: 4ef0d5854df39c57605e59bb6d255215cc85468a
2019-10-04T11:19:47.109454132Z 
2019-10-04T11:19:47.115741747Z Cound not find build manifest file at '/home/site/wwwroot/oryx-manifest.toml'
2019-10-04T11:19:47.116226163Z Could not find operation ID in manifest. Generating an operation id...
2019-10-04T11:19:47.116765782Z Build Operation ID: d07e7783-8975-4038-8eaa-4e7987fbfe37
2019-10-04T11:19:47.890841571Z Writing output script to '/opt/startup/startup.sh'
2019-10-04T11:19:47.896506064Z Running #!/bin/sh
2019-10-04T11:19:47.897427996Z 
2019-10-04T11:19:47.897445097Z # Enter the source directory to make sure the script runs where the user expects
2019-10-04T11:19:47.898696539Z cd "/home/site/wwwroot"
2019-10-04T11:19:47.898713540Z 
2019-10-04T11:19:47.899855479Z if [ -z "$PORT" ]; then
2019-10-04T11:19:47.900292094Z         export PORT=8080
2019-10-04T11:19:47.900308195Z fi
2019-10-04T11:19:47.901053620Z 
2019-10-04T11:19:47.901069221Z npm start
2019-10-04T11:19:48.909373625Z 
2019-10-04T11:19:48.909490829Z > appname@0.0.0 start /home/site/wwwroot
2019-10-04T11:19:48.909499129Z > ng serve
2019-10-04T11:19:48.909512530Z 
2019-10-04T11:19:49.177294093Z internal/modules/cjs/loader.js:583
2019-10-04T11:19:49.177326694Z     throw err;
2019-10-04T11:19:49.177333094Z     ^
2019-10-04T11:19:49.177336894Z 
2019-10-04T11:19:49.177340595Z Error: Cannot find module '../lib/init'
2019-10-04T11:19:49.177344395Z     at Function.Module._resolveFilename (internal/modules/cjs/loader.js:581:15)
2019-10-04T11:19:49.177348395Z     at Function.Module._load (internal/modules/cjs/loader.js:507:25)
2019-10-04T11:19:49.177360595Z     at Module.require (internal/modules/cjs/loader.js:637:17)
2019-10-04T11:19:49.177364695Z     at require (internal/modules/cjs/helpers.js:20:18)
2019-10-04T11:19:49.177368396Z     at Object. (/home/site/wwwroot/node_modules/.bin/ng:25:1)
2019-10-04T11:19:49.177372596Z     at Module._compile (internal/modules/cjs/loader.js:689:30)
2019-10-04T11:19:49.177376196Z     at Object.Module._extensions..js (internal/modules/cjs/loader.js:700:10)
2019-10-04T11:19:49.177379896Z     at Module.load (internal/modules/cjs/loader.js:599:32)
2019-10-04T11:19:49.177383596Z     at tryModuleLoad (internal/modules/cjs/loader.js:538:12)
2019-10-04T11:19:49.177387196Z     at Function.Module._load (internal/modules/cjs/loader.js:530:3)
2019-10-04T11:19:49.188853589Z npm ERR! code ELIFECYCLE
2019-10-04T11:19:49.190238236Z npm ERR! errno 1
2019-10-04T11:19:49.193511748Z npm ERR! appname@0.0.0 start: `ng serve`
2019-10-04T11:19:49.194584885Z npm ERR! Exit status 1
2019-10-04T11:19:49.196721058Z npm ERR! 
2019-10-04T11:19:49.197268977Z npm ERR! Failed at the appname@0.0.0 start script.
2019-10-04T11:19:49.197998301Z npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
2019-10-04T11:19:49.205773868Z 
2019-10-04T11:19:49.206361388Z npm ERR! A complete log of this run can be found in:
2019-10-04T11:19:49.206880405Z npm ERR!     /root/.npm/_logs/2019-10-04T11_19_49_199Z-debug.log

The YML file that is used for the build and deploy stages is as follows:

variables:

  # Agent VM image name
  vmImageName: 'ubuntu-latest'

stages:
- stage: Build
  displayName: Build stage
  jobs:  
  - job: Build
    displayName: Build
    pool:
      vmImage: $(vmImageName)

    steps:
    - task: NodeTool@0
      inputs:
        versionSpec: '10.x'
      displayName: 'Install Node.js'

    - script: |
        npm install -g @angular/cli
        npm install
        npm run build
      displayName: 'npm install and build'

    - task: ArchiveFiles@2
      displayName: 'Archive files'
      inputs:
        rootFolderOrFile: '$(System.DefaultWorkingDirectory)'
        includeRootFolder: false
        archiveType: 'zip'
        archiveFile: $(Build.ArtifactStagingDirectory)/$(Build.BuildId).zip
        replaceExistingArchive: true

    - upload: $(Build.ArtifactStagingDirectory)/$(Build.BuildId).zip
      artifact: drop

- stage: Deploy
  displayName: Deploy stage
  dependsOn: Build
  condition: succeeded()
  jobs:
  - deployment: Deploy
    displayName: Deploy
    environment: $(environmentName)
    pool: 
      vmImage: $(vmImageName)
    strategy:
      runOnce:
        deploy:
          steps:            
          - task: AzureWebApp@1
            displayName: 'Azure Web App Deploy: appname'
            inputs:
              azureSubscription: $(azureSubscription)
              appType: webAppLinux
              appName: $(webAppName)
              runtimeStack: 'NODE|10.10'
              package: $(Pipeline.Workspace)/drop/$(Build.BuildId).zip
              startUpCommand: 'npm start'

I've tried running other commands to reinstall npm or to drop the node_modules but that didn't resolve the issue. Please help since I'm clueless on how to make this work.