Release gax-java v1.53.2

[chingor13]

This pull request was generated using releasetool.

02-24-2020 13:16 PST

Implementation Changes

• Scale number of threads to scale with number of cpus (#878)
• Do not shut down executor when WatchDog is shut down (#871)

Documentation

• Add javadoc about being called within single thread (#856)

[codecov]

Codecov Report

Merging #880 into master will decrease coverage by 0.01%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master     #880      +/-   ##
============================================
- Coverage     78.63%   78.61%   -0.02%     
+ Complexity     1163     1162       -1     
============================================
  Files           203      203              
  Lines          5143     5143              
  Branches        413      413              
============================================
- Hits           4044     4043       -1     
  Misses          925      925              
- Partials        174      175       +1

Impacted Files	Coverage Δ	Complexity Δ
.../java/com/google/api/gax/batching/BatcherImpl.java	97.33% <0%> (-0.67%)	15% <0%> (-1%)

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[igorbernstein2]

This should be 1.54.0 since this is changing default behavior