Disable "withdraw-all-rewards" command when "--generate-only" is supplied

[alexanderbez]

closes: #4870

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• Wrote tests

• Updated relevant documentation (docs/)

• Added a relevant changelog entry: clog add [section] [-t <tag>] [-m <msg>]

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For Admin Use:

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[codecov]

Codecov Report

Merging #4872 into master will decrease coverage by 0.01%.
The diff coverage is 0%.

@@            Coverage Diff             @@
##           master    #4872      +/-   ##
==========================================
- Coverage   54.31%   54.29%   -0.02%     
==========================================
  Files         271      271              
  Lines       17344    17346       +2     
==========================================
- Hits         9420     9418       -2     
- Misses       7226     7230       +4     
  Partials      698      698