chore: release 1.102.0

[release-please]

🤖 I have created a release *beep* *boop*

1.102.0 (2020-06-02)

Features

• add flatten plugin to client and proto modules (#108) (fb3566d)
• Create CODEOWNERS (#122) (8082369)
• implement google-cloud-shared-dependencies BOM (#135) (72e29ff)

Bug Fixes

• update retry logic for operations that can be associated with a transaction (#144) (82ee74e)

Dependencies

• bump shared-deps version and add back certain test deps (#139) (660f216)
• update core transport dependencies to v1.35.0 (#114) (cad3bfb)
• update dependency com.google.api.grpc:proto-google-common-protos to v1.18.0 (#117) (b484256)
• update dependency com.google.cloud:google-cloud-shared-dependencies to v0.6.0 (#140) (712779c)
• update dependency com.google.cloud:google-cloud-shared-dependencies to v0.7.0 (#142) (e1a5a65)
• update dependency com.google.guava:guava-bom to v29 (#95) (32d5e37)
• update dependency com.google.protobuf:protobuf-java to v3.12.0 (#127) (8a310f3)
• update dependency io.grpc:grpc-bom to v1.29.0 (#110) (ad6b880)
• update dependency org.threeten:threetenbp to v1.4.4 (#112) (41d571d)

Documentation

• fix java doc link of LocalDatastoreHelper#stop (#126) (ed9b895)
• update CONTRIBUTING.md to include code formatting (#534) (#124) (147197d)

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This PR was generated with Release Please.

[yoshi-automation]

Release is at https://github.com/googleapis/java-datastore/releases/tag/v1.102.0

[BenWhitehead]

I've manually verified that the release to maven central happened, and the reporting back to this PR failed due to the automation proxy.