chore: release 2.1.0

[release-please]

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

2.1.0 (2021-04-23)

Features

• Added legacy_sku field to TransferableSku (3e0defe)
• Adding customer level pubsub events for primary domain verification and primary domain change (3e0defe)
• addition of billing_account field on Plan (#56) (fdc2ad6)
• Enabled support for boolean as an allowed parameter value (3e0defe)
• generator: update protoc to v3.15.3 (#54) (bcece47)

Bug Fixes

• release scripts from issuing overlapping phases (#74) (72667e2)
• typo (#72) (dc27217)

Documentation

• clarification that valid address lines are required for all customers (fdc2ad6)
• Update documentation comments to match tone and style with the rest of Cloud documentation (#69) (3e0defe)

Dependencies

• update dependency com.google.cloud:google-cloud-shared-dependencies to v0.20.1 (#61) (b532007)
• update dependency com.google.cloud:google-cloud-shared-dependencies to v0.21.0 (#70) (93fde13)
• update dependency com.google.cloud:google-cloud-shared-dependencies to v0.21.1 (#75) (5686118)
• update dependency com.google.cloud:google-cloud-shared-dependencies to v1 (#79) (84f0ac3)

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This PR was generated with Release Please. See documentation.

[codecov]

Codecov Report

Merging #55 (abb2f4b) into master (84f0ac3) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master      #55   +/-   ##
=========================================
  Coverage     82.50%   82.50%           
  Complexity      177      177           
=========================================
  Files             6        6           
  Lines          2183     2183           
  Branches         12       12           
=========================================
  Hits           1801     1801           
  Misses          366      366           
  Partials         16       16           

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[yoshi-automation]

🤖 Release is at https://github.com/googleapis/java-channel/releases/tag/v2.1.0 🌻

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[release-tool-publish-reporter]

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