added type annotations to pl_bolts/optimizers

[johnpeterson123]

What does this PR do?

Part of #434

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[pep8speaks]

Hello @johnpeterson123! Thanks for opening this PR.

• In the file pl_bolts/optimizers/lr_scheduler.py:

Line 92:15: W503 line break before binary operator
Line 102:70: W504 line break after binary operator
Line 105:15: W504 line break after binary operator
Line 108:74: W504 line break after binary operator
Line 121:56: W504 line break after binary operator
Line 122:50: W504 line break after binary operator
Line 130:70: W504 line break after binary operator

Do see the Hitchhiker's guide to code style

[codecov]

Codecov Report

Merging #608 (4410327) into master (9044ed1) will increase coverage by 0.06%.
The diff coverage is 86.36%.

@@            Coverage Diff             @@
##           master     #608      +/-   ##
==========================================
+ Coverage   25.20%   25.26%   +0.06%     
==========================================
  Files         118      118              
  Lines        7119     7125       +6     
==========================================
+ Hits         1794     1800       +6     
  Misses       5325     5325              

Flag	Coverage Δ
cpu	25.26% <86.36%> (+0.06%)	⬆️
pytest	25.26% <86.36%> (+0.06%)	⬆️

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Impacted Files	Coverage Δ
pl_bolts/optimizers/lars_scheduling.py	35.84% <76.92%> (+8.18%)	⬆️
pl_bolts/optimizers/lr_scheduler.py	93.10% <100.00%> (ø)

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[Borda]

@johnpeterson123 mind check review comments and conflicts? 🐰

[Borda]

@johnpeterson123 how is it going here? mind resolve conflicts? 🐰

[Borda]

@SeanNaren mind check it if we can quick let it land, otherwise we may close it as @johnpeterson123 is not responding

[SeanNaren]

@Borda not sure we should add so many ignores as @akihironitta mentions in #434 (comment)

Is there a way to do this typing without all these ignores?

[akihironitta]

Feel free to reopen this PR if needed.