Update resume_from_checkpoint docs

[carmocca]

What does this PR do?

Fixes #7072

Does your PR introduce any breaking changes? If yes, please list them.

None

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• [n/a] Did you write any new necessary tests? (not for typos and docs)
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[codecov]

Codecov Report

Merging #9952 (6487b81) into master (6429de8) will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff           @@
##           master   #9952   +/-   ##
======================================
  Coverage      89%     89%           
======================================
  Files         179     179           
  Lines       15831   15831           
======================================
  Hits        14053   14053           
  Misses       1778    1778           

[tchaton]

LGMT !