docs: add docs tag for dependency (#374)
docs: add docs tag for dependency (#374)

Adds a tag to the dependency example in the README file, so this can be
reused in the Cloud documentation.
GoogleCloudPlatform/pgadapter,GoogleCloudPlatform/pgadapter,GoogleCloudPlatform/pgadapter,GoogleCloudPlatform/pgadapter,GoogleCloudPlatform/pgadapter,GoogleCloudPlatform/pgadapter,GoogleCloudPlatform/pgadapter