Add MemoryFormat callback (channels last)

[Pedrexus]

What does this PR do?

This PR fixes issue #15175 by adding a new feature to the ChannelsLast callback. This callback changes the module memory format on setup. This is useful when the user wants to use a different memory format and can lead to a considerable speedup in some cases.

Fixes #15175

This PR does not introduce any breaking changes.

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[Pedrexus]

Hello, all. I'm having trouble running make docs. I'd be glad if someone could help.

Error:
ModuleNotFoundError: No module named 'pt_lightning_sphinx_theme'

[awaelchli]

@Pedrexus This should get you started:

pip install -r requirements/pytorch/docs.txt
cd docs/source-pytorch
make html 
open ../build/html/index.html

Also, I left a comment here: #15175 (comment)

[codecov]

Codecov Report

Attention: Patch coverage is 89.65517% with 3 lines in your changes missing coverage. Please review.

Project coverage is 49%. Comparing base (e040ef2) to head (10bd4f5).
Report is 467 commits behind head on master.

❗ There is a different number of reports uploaded between BASE (e040ef2) and HEAD (10bd4f5). Click for more details.

HEAD has 505 uploads less than BASE

Flag	BASE (e040ef2)	HEAD (10bd4f5)
lightning	88	16
cpu	148	24
pytest	104	2
python3.10	41	9
app	9	0
examples	9	0
python3.9	14	3
lightning_fabric	26	0
python3.8	28	6
python3.11	35	6
gpu	4	2
pytest-full	48	24
pytorch1.13	12	6
pytorch1.12	12	6
pytorch_lightning	19	10
pytorch2.0	12	6
pytorch2.1	12	6
lightning_app	10	0

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #17680      +/-   ##
==========================================
- Coverage      83%      49%     -34%     
==========================================
  Files         445      438       -7     
  Lines       37305    37181     -124     
==========================================
- Hits        31005    18270   -12735     
- Misses       6300    18911   +12611     

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