Replace DP/DDP/DDPSpawn plugins to strategies, keep the old for compatibility

[krshrimali]

What does this PR do?

Error:

File "/opt/hostedtoolcache/Python/3.8.13/x64/lib/python3.8/site-packages/flash/image/classification/adapters.py", line 23, in <module>
    from pytorch_lightning.plugins import DataParallelPlugin, DDPPlugin, DDPSpawnPlugin
ImportError: cannot import name 'DataParallelPlugin' from 'pytorch_lightning.plugins' 

PL 1.6.0 had removed these plugins, in the favor of strategies. This PR makes sure to not break the compatibility for older PL versions, and making sure to support latest PL API.

Before submitting

• Was this discussed/approved via a Github issue? (no need for typos and docs improvements)
• Did you read the contributor guideline, Pull Request section?
• Did you make sure your PR does only one thing, instead of bundling different changes together?
• Did you make sure to update the documentation with your changes?
• Did you write any new necessary tests? [not needed for typos/docs]
• Did you verify new and existing tests pass locally with your changes?
• If you made a notable change (that affects users), did you update the CHANGELOG?

PR review

• Is this pull request ready for review? (if not, please submit in draft mode)

Anyone in the community is free to review the PR once the tests have passed.
If we didn't discuss your PR in Github issues there's a high chance it will not be merged.

Did you have fun?

Make sure you had fun coding 🙃

[ethanwharris]

LGTM 😃

[codecov]

Codecov Report

Merging #1451 (6575f40) into master (da42a63) will decrease coverage by 0.55%.
The diff coverage is 83.33%.

@@            Coverage Diff             @@
##           master    #1451      +/-   ##
==========================================
- Coverage   92.84%   92.29%   -0.56%     
==========================================
  Files         287      287              
  Lines       12975    13061      +86     
==========================================
+ Hits        12046    12054       +8     
- Misses        929     1007      +78     

Flag	Coverage Δ
pytest	13.29% <0.00%> (?)
tpu	13.29% <0.00%> (?)
unittests	92.82% <83.33%> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
flash/image/classification/adapters.py	82.53% <83.33%> (-1.42%)	⬇️
flash/image/segmentation/cli.py	83.33% <0.00%> (-16.67%)	⬇️
flash/pointcloud/detection/cli.py	83.33% <0.00%> (-16.67%)	⬇️
flash/pointcloud/segmentation/cli.py	83.33% <0.00%> (-16.67%)	⬇️
flash/text/question_answering/cli.py	83.33% <0.00%> (-16.67%)	⬇️
flash/audio/speech_recognition/cli.py	83.33% <0.00%> (-16.67%)	⬇️
flash/text/seq2seq/summarization/cli.py	83.33% <0.00%> (-16.67%)	⬇️
flash/image/detection/cli.py	84.61% <0.00%> (-15.39%)	⬇️
flash/audio/classification/cli.py	84.61% <0.00%> (-15.39%)	⬇️
flash/video/classification/cli.py	84.61% <0.00%> (-15.39%)	⬇️
... and 28 more

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.

[krshrimali]

The failing test is flaky (and not related to this PR), from an offline discussion with @ethanwharris:

We would just need to use a different random seed where it performs better.

For now, merging this PR. 🔥