deps: update gax.version to v1.49.0, guava to 28.1-android (#13)
deps: update gax.version to v1.49.0, guava to 28.1-android (#13)

* chore(deps): update gax.version to v1.49.0

* deps: update guava to 28.1-android

* deps: specify version for animal-sniffer-annotations

googleapis/google-cloud-java,googleapis/google-cloud-java,googleapis/google-cloud-java