Currently, GCS objects get created with content type as octet-stream. Support should be added to allow users to specify the content type. A dropdown widget that displays common content types should be used, but in addition, users should be able to also type in their own content type.
UI: Add a filter flag and 2 different filter dropdown with GCS create. last item in the drop down is custom which will show a new widget field to fill out the custom value.
This change should add integration test for gcs sink and gcs multi sink as well. Please merge integration test PR as well before marking this task as completed