GIThub api only update the teams under push restrictions

I am writing a code in powershell to update the teams who can push to matching branches So when i write the below code in this way it works but i only want to update the teams and i dont want to update any other branch protection rules. How can i achieve that?

Code which works and which also updates the whole branch protection rule if i keep the below json body into

  $jsonBody = '
        {
            "required_pull_request_reviews": {
                "dismiss_stale_reviews": false,
                "require_code_owner_reviews": false,
                "required_approving_review_count": 2
            },
            "enforce_admins": false,
            "required_status_checks" : null,
            "restrictions": {
            "users": [],
            "teams": ["test"],
            "apps": []
            }
        }'

$response = Invoke-WebRequest -Uri "https://github.source.internal/api/v3/$repos/cds/Api.testbpr/branches/master/protection" -Method Put -Body $body -ContentType "application/json" `
                                -Headers @{"Authorization"=$headerString; `
                                "Accept"="application/vnd.github.luke-cage-preview+json" } `
                                -TimeoutSec 300  -UseBasicParsing  

The above code works and updates the whole branch protection rule but what i need to achieve is that i just want to add a team under restrictions and i tried the below code but it throws error

   $response = Invoke-WebRequest -Uri "https://github.source.internal/api/v3/$repos/cds/Api.testbpr/branches/master/protection/restrictions/teams" -Method Put -Body '{"teams":["test"]}' -ContentType "application/json" `
                                -Headers @{"Authorization"=$headerString; `
                                "Accept"="application/vnd.github.luke-cage-preview+json" } `
                                -TimeoutSec 300  -UseBasicParsing  

Error : Invoke-WebRequest : {"message":"Invalid request.\n\nFor 'links/9/schema', {\"teams\"=>[\"teams\"]} is not an 
array.","documentation_url":"https://docs.github.com/enterprise/3.5/rest/reference/repos#add-team-access-restrictions"}