Retry RequestTimeout error by S3.

[waahm7]

Description of changes:

• S3 can kill the request with a 400 status code and the error code RequestTimeout. We should retry the request since other SDKs also treat this error as retryable.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.73%. Comparing base (ab70f74) to head (934f3e9).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #457      +/-   ##
==========================================
+ Coverage   89.30%   89.73%   +0.42%     
==========================================
  Files          20       20              
  Lines        6132     6154      +22     
==========================================
+ Hits         5476     5522      +46     
+ Misses        656      632      -24     

Files with missing lines	Coverage Δ
source/s3.c	98.46% <ø> (ø)
source/s3_util.c	97.16% <100.00%> (+<0.01%)	⬆️

... and 3 files with indirect coverage changes