Remove type error handling in _configure_checkpoint_callbacks

[daniellepintz]

What does this PR do?

Resolving a TODO in the code for v1.5

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[tchaton]

LGMT !

[codecov]

Codecov Report

Merging #9823 (9e0b42f) into master (dc27c72) will decrease coverage by 4%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #9823    +/-   ##
=======================================
- Coverage      93%     89%    -4%     
=======================================
  Files         178     178            
  Lines       15650   15645     -5     
=======================================
- Hits        14508   13894   -614     
- Misses       1142    1751   +609