Fail LocalFilesystemToGCSOperator if src does not exist

[pankajastro]

Fix #22705.

Fail LocalFilesystemToGCSOperator if the src file does not exist

src argument of LocalFilesystemToGCSOperator accept either list of source file path or a single source file path as a string. In the case of a single source file path we are using glob to parse the file path and glob return empty list if file path does not exist. In the next step, we iterate on this list and call hook api to update the file since the list is empty control is not going inside loop and task is succeeding even if the source file is not available.

Change

• Raise an exception if filepath list is empty

After this change below task will fail if example-text.txt does not exist

upload_file = LocalFilesystemToGCSOperator(
        task_id="upload_file",
        src="example-text.txt",
        dst=DESTINATION_FILE_LOCATION,
        bucket=BUCKET_NAME,
    )

@kaxil @phanikumv

[boring-cyborg]

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[phanikumv]

Please include a test for this additional logic here

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

[boring-cyborg]

Awesome work, congrats on your first merged pull request!