chore: release 2.4.0

[release-please]

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

2.4.0 (2021-04-23)

Features

• Add fields for Pub/Sub triggers (#457) (55b10de)

Bug Fixes

• release scripts from issuing overlapping phases (#456) (ad05975)
• typo (#453) (dffb9db)

Dependencies

• update dependency com.google.cloud:google-cloud-shared-dependencies to v0.21.1 (#460) (d34cd4d)
• update dependency com.google.cloud:google-cloud-shared-dependencies to v1 (#463) (82711b3)

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This PR was generated with Release Please. See documentation.

[codecov]

Codecov Report

Merging #454 (0d4c70f) into master (82711b3) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master     #454   +/-   ##
=========================================
  Coverage     82.68%   82.68%           
  Complexity      121      121           
=========================================
  Files             6        6           
  Lines           976      976           
  Branches          3        3           
=========================================
  Hits            807      807           
  Misses          166      166           
  Partials          3        3           

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[yoshi-automation]

🤖 Release is at https://github.com/googleapis/java-cloudbuild/releases/tag/v2.4.0 🌻

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The release build has started, the log can be viewed here. 🌻

[release-tool-publish-reporter]

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