chore: release 1.19.0

[release-please]

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

1.19.0 (2021-04-15)

⚠ BREAKING CHANGES

• remove v1alpha2 library (refactor!: remove v1alpha2 library #1003)

Bug Fixes

• release scripts from issuing overlapping phases (#1006) (f338201)

Code Refactoring

• remove v1alpha2 library (#1003) (98cd924)

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[codecov]

Codecov Report

Merging #1007 (2531838) into master (98cd924) will decrease coverage by 0.02%.
The diff coverage is n/a.

❗ Current head 2531838 differs from pull request most recent head 43f3d55. Consider uploading reports for the commit 43f3d55 to get more accurate results

@@             Coverage Diff              @@
##             master    #1007      +/-   ##
============================================
- Coverage     80.13%   80.10%   -0.03%     
  Complexity      710      710              
============================================
  Files            61       61              
  Lines          3961     3961              
  Branches        264      264              
============================================
- Hits           3174     3173       -1     
- Misses          663      664       +1     
  Partials        124      124              

Impacted Files	Coverage Δ	Complexity Δ
...e/cloud/bigquery/storage/v1beta2/StreamWriter.java	83.25% <0.00%> (-0.23%)	33.00% <0.00%> (ø%)

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[yoshi-automation]

🤖 Release is at https://github.com/googleapis/java-bigquerystorage/releases/tag/v1.19.0 🌻

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[release-tool-publish-reporter]

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