Fix mypy errors attributed to `pytorch_lightning.trainer.connectors.data_connector.py`

[jxtngx]

What does this PR do?

Fix mypy errors attributed to pytorch_lightning.trainer.connectors.data_connector.py for issue #13445

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

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[codecov[bot]]

Codecov Report

Merging #13806 (ec1702e) into master (70fe0ed) will decrease coverage by 3%. The diff coverage is 100%.

:exclamation: Current head ec1702e differs from pull request most recent head 8fa58a8. Consider uploading reports for the commit 8fa58a8 to get more accurate results

@@            Coverage Diff             @@
##           master   #13806      +/-   ##
==========================================
- Coverage      79%      76%      -3%     
==========================================
  Files         111      332     +221     
  Lines        7258    26897   +19639     
==========================================
+ Hits         5740    20435   +14695     
- Misses       1518     6462    +4944     

[rohitgr7]

messed up somewhere :p will check tomorrow!

[jxtngx]

apologies, I'm no longer able to keep this PR up to date.

[otaj]

@JustinGoheen, we're sorry to hear that. @rohitgr7, are you gonna push it over the finish line or should I? I noticed you started pushing some commits :zap:

[rohitgr7]

@otaj it's done. Any things else needs to be done here? The CI is blocking the merge for now

[otaj]

@rohitgr7, awesome, thank you! :tada:. I guess we just have to wait on codeowners and CI