Add lightning flash tutorials

[krshrimali]

Before submitting

• [x] Was this discussed/approved via a Github issue? (no need for typos and docs improvements)
• [x] Did you make sure to update the docs?
• [x] Did you write any new necessary tests?

What does this PR do?

Fixes # (issue)

PR review

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 🙃

cc: @ethanwharris

[review-notebook-app[bot]]

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[codecov[bot]]

Codecov Report

Merging #183 (9da4b08) into main (b51741e) will not change coverage. The diff coverage is n/a.

@@         Coverage Diff         @@
##           main   #183   +/-   ##
===================================
  Coverage    75%    75%           
===================================
  Files         2      2           
  Lines       370    370           
===================================
  Hits        276    276           
  Misses       94     94           

[krshrimali]

@Borda - PTAL. :)