chore(deps): update dependency google-cloud-bigtable to v1.6.0 (#4987)
chore(deps): update dependency google-cloud-bigtable to v1.6.0 (#4987)


GoogleCloudPlatform/python-docs-samples,GoogleCloudPlatform/python-docs-samples,GoogleCloudPlatform/python-docs-samples,GoogleCloudPlatform/python-docs-samples