Backports replicas change and rollover RTE cause handling

[dbbaughe]

Issue #, if available:

Description of changes:

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

[codecov]

Codecov Report

Merging #327 (866165c) into opendistro-1.8 (316535a) will increase coverage by 0.10%.
The diff coverage is 33.33%.

@@                 Coverage Diff                  @@
##             opendistro-1.8     #327      +/-   ##
====================================================
+ Coverage             75.01%   75.11%   +0.10%     
  Complexity              666      666              
====================================================
  Files                    83       83              
  Lines                  3758     3758              
  Branches                608      607       -1     
====================================================
+ Hits                   2819     2823       +4     
+ Misses                  627      623       -4     
  Partials                312      312              

Impacted Files	Coverage Δ	Complexity Δ
...atemanagement/step/rollover/AttemptRolloverStep.kt	55.65% <0.00%> (+0.95%)	14.00 <0.00> (ø)
...ndexstatemanagement/IndexStateManagementHistory.kt	75.96% <100.00%> (+0.23%)	27.00 <0.00> (ø)
...ndexstatemanagement/IndexStateManagementIndices.kt	65.51% <100.00%> (+4.11%)	10.00 <0.00> (ø)

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