Fix access to logger attribute when multiple loggers are used

[awaelchli]

What does this PR do?

Fixes #14231

To be included in 1.7.x. The code we fix here will also be removed later on as part of the deprecation ending in 1.8.

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Did you have fun?

I made sure I had fun coding 🙃

cc @awaelchli @edward-io @Borda @ananthsub @rohitgr7 @kamil-kaczmarek @Raalsky @Blaizzy @carmocca @justusschock @ninginthecloud @jjenniferdai

[codecov]

Codecov Report

Merging #14234 (5880e28) into master (047f0aa) will decrease coverage by 9%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master   #14234     +/-   ##
=========================================
- Coverage      85%      76%     -9%     
=========================================
  Files         330      330             
  Lines       26760    26761      +1     
=========================================
- Hits        22797    20348   -2449     
- Misses       3963     6413   +2450