Support deprecated attribute usage

[carmocca]

What does this PR do?

Reported in Slack by Tran N.M. Hoang

Hi, I have met a bug when using lightning v1.4 and lightning-bolts to train Moco_v2, it seems that since lightning v1.4, self.trainer.use_ddp2 and self.trainer.use_ddp are removed but Moco_v2 implemented by lightning-bolts stills uses this functionality, so I cannot train Moco_v2 anymore. Can you check it?

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[codecov]

Codecov Report

Merging #699 (82d080e) into master (73f2f99) will decrease coverage by 0.43%.
The diff coverage is 89.47%.

@@            Coverage Diff             @@
##           master     #699      +/-   ##
==========================================
- Coverage   72.03%   71.60%   -0.44%     
==========================================
  Files         119      119              
  Lines        7356     7367      +11     
==========================================
- Hits         5299     5275      -24     
- Misses       2057     2092      +35     

Flag	Coverage Δ
cpu	71.60% <89.47%> (-0.44%)	⬇️
pytest	71.60% <89.47%> (-0.44%)	⬇️

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

Impacted Files	Coverage Δ
pl_bolts/models/rl/dqn_model.py	80.44% <85.71%> (-0.02%)	⬇️
..._bolts/models/self_supervised/moco/moco2_module.py	59.42% <88.88%> (+0.60%)	⬆️
pl_bolts/models/rl/double_dqn_model.py	95.83% <100.00%> (ø)
pl_bolts/models/rl/per_dqn_model.py	86.88% <100.00%> (ø)
pl_bolts/utils/__init__.py	92.85% <100.00%> (+0.26%)	⬆️
pl_bolts/datasets/cifar10_dataset.py	72.04% <0.00%> (-25.81%)	⬇️
pl_bolts/datasets/base_dataset.py	81.39% <0.00%> (-13.96%)	⬇️
...l_bolts/models/rl/vanilla_policy_gradient_model.py	93.44% <0.00%> (-2.46%)	⬇️

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