chore: release 0.20.0

[release-please]

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

0.20.0 (2020-07-22)

⚠ BREAKING CHANGES

• remove v1alpha client (feat!: remove v1alpha client #177)

Features

• deps: adopt flatten plugin and google-cloud-shared-dependencies (#159) (871c822)
• add v1beta client (#176) (d818dd4)
• remove v1alpha client (#177) (948776f)

Dependencies

• update dependency com.google.api:api-common to v1.9.1 (#138) (6e0743e)
• update dependency com.google.api:api-common to v1.9.2 (#143) (0a794e9)
• update dependency com.google.api.grpc:proto-google-common-protos to v1.18.0 (#129) (9bd660b)
• update dependency com.google.cloud:google-cloud-shared-dependencies to v0.8.2 (#171) (043e1c0)
• update dependency com.google.cloud:google-cloud-shared-dependencies to v0.8.3 (#173) (eeb1a1b)
• update dependency com.google.guava:guava-bom to v29 (#107) (5d8453f)
• update dependency com.google.protobuf:protobuf-java to v3.12.0 (#132) (3976e6f)
• update dependency com.google.protobuf:protobuf-java to v3.12.2 (#136) (3722284)
• update dependency io.grpc:grpc-bom to v1.29.0 (#121) (1a3260b)
• update dependency io.grpc:grpc-bom to v1.30.0 (#147) (a715575)
• update dependency org.threeten:threetenbp to v1.4.4 (#125) (ce50084)

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This PR was generated with Release Please.

[codecov]

Codecov Report

Merging #161 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #161   +/-   ##
=========================================
  Coverage     75.10%   75.10%           
  Complexity      274      274           
=========================================
  Files            24       24           
  Lines          2470     2470           
  Branches         22       22           
=========================================
  Hits           1855     1855           
  Misses          587      587           
  Partials         28       28           

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[yoshi-automation]

Release is at https://github.com/googleapis/java-game-servers/releases/tag/v0.20.0