Remove debugging_connector.py

[daniellepintz]

What does this PR do?

Fixes #10109

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

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[tchaton]

LGMT !

[codecov]

Codecov Report

Merging #10113 (b4617e8) into master (dbe1662) will decrease coverage by 0%.
The diff coverage is 100%.

❗ Current head b4617e8 differs from pull request most recent head 2350854. Consider uploading reports for the commit 2350854 to get more accurate results

@@           Coverage Diff           @@
##           master   #10113   +/-   ##
=======================================
- Coverage      89%      89%   -0%     
=======================================
  Files         180      181    +1     
  Lines       16146    16102   -44     
=======================================
- Hits        14317    14265   -52     
- Misses       1829     1837    +8     

[daniellepintz]

I am confused why mypy is failing:
pytorch_lightning/plugins/precision/precision_plugin.py:147: error: Cannot determine type of "track_grad_norm" [has-type]
anyone have any ideas? It seems to have to do with #10112, but I don't see what the problem is

[carmocca]

@daniellepintz Fixed by merging master 🤗