fix(deps): set gson via java-shared-deps

[suztomo]

Gson dependency version should be set by the java-shared-dependencies BOM, so that the artifacts listed in the google-cloud-bom have the same set of the dependencies.

This should fix one of the problems in googleapis/java-cloud-bom#3593 (comment).

CC: @Neenu1995

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Fixes #<issue_number_goes_here> ☕️

[suztomo]

"Environment - Functions" failed but it's not a required check.

+ /tmpfs/src/github/java-logging/env-tests-logging/envctl/envctl java functions destroy
Error: not a valid environment: functions

Select a supported GCP environment.

[suztomo]

Integration test failed: https://source.cloud.google.com/results/invocations/bdbdf260-4bd8-4eb3-bde5-e79aba043a7e/targets/github%2Fjava-logging%2Fgoogle-cloud-logging%2Ftarget%2Ffailsafe-reports%2Fintegration%2Fcom.google.cloud.logging.it.ITTailLogsTest/tests

com.google.api.gax.rpc.ResourceExhaustedException: io.grpc.StatusRuntimeException: RESOURCE_EXHAUSTED: Quota exceeded for quota metric 'Read requests' and limit 'Read requests per minute' of service 'logging.googleapis.com' for consumer 'project_number:1016721519174'.