CDK python lambda gets bundled every time I run a cdk command

I'm using CDK in python to deploy a Lambda function

from aws_cdk import (
    core,
    aws_lambda as _lambda
)

class MyLambdaStack(core.Stack):
    def __init__(self, id, scope: core.Construct, **kwargs) -> None:
        super().__init__(id, scope, **kwargs)

        my_function = _lambda.Function(self, "MyLambda",
            runtime=_lambda.Runtime.PYTHON_3_8,
            handler="MyLambda.handler",
            code=_lambda.Code.from_asset(
                './lambda',
                bundling=core.BundlingOptions(
                    image=_lambda.Runtime.PYTHON_3_8.bundling_docker_image,
                    command=[
                        'bash', '-c', 'pip install -r requirements.txt -t /asset-output && cp -au . /asset-output'
                    ],
                )
            )
        )

The bundling works fine, however every time I run a cdk command, the docker image gets spun up and the pip install command runs.

Even a cdk ls causes the bundle to run.

How can I prevent this from running during every cdk command?