[Feat] 2/n Add Fault Tolerant Training to LightningFetcher

[tchaton]

What does this PR do?

This PR adds fault tolerant support to the LightningFetcher.

Blocked by #8890

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Did you have fun?

I made sure I had fun coding 🙃

[codecov]

Codecov Report

Merging #8891 (0254043) into master (de22e40) will decrease coverage by 5%.
The diff coverage is 52%.

@@           Coverage Diff           @@
##           master   #8891    +/-   ##
=======================================
- Coverage      93%     88%    -5%     
=======================================
  Files         176     176            
  Lines       14270   14394   +124     
=======================================
- Hits        13260   12695   -565     
- Misses       1010    1699   +689