fix: Modify CommitterImpl to exit early in case of permanent failure

[dpcollins-google]

This avoids waiting on its own actions to complete if one of the commit futures returned by abort() calls stopAsync on the committer.

[codecov]

Codecov Report

Merging #90 into master will increase coverage by 0.33%.
The diff coverage is 66.66%.

@@             Coverage Diff              @@
##             master      #90      +/-   ##
============================================
+ Coverage     59.78%   60.11%   +0.33%     
- Complexity      386      388       +2     
============================================
  Files            90       90              
  Lines          2044     2046       +2     
  Branches        170      170              
============================================
+ Hits           1222     1230       +8     
+ Misses          731      724       -7     
- Partials         91       92       +1     

Impacted Files	Coverage Δ	Complexity Δ
.../cloud/pubsublite/internal/wire/CommitterImpl.java	65.30% <66.66%> (-0.66%)	8.00 <0.00> (ø)
...oogle/cloud/pubsublite/internal/ExtractStatus.java	72.22% <0.00%> (+38.88%)	6.00% <0.00%> (+2.00%)

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