Add updateWith method to NonEmptyMap

[nasadorian]

• Named updateWith since updated would imply a simple setting of k -> v
• Added a couple small tests

Closes #2288

[nasadorian]

Build is flaky? Seems to have died with OOM for Scala 2.13...

[codecov-io]

Codecov Report

Merging #2592 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #2592      +/-   ##
==========================================
+ Coverage   95.16%   95.16%   +<.01%     
==========================================
  Files         361      361              
  Lines        6634     6637       +3     
  Branches      294      290       -4     
==========================================
+ Hits         6313     6316       +3     
  Misses        321      321

Impacted Files	Coverage Δ
...ore/src/main/scala/cats/data/NonEmptyMapImpl.scala	96.15% <100%> (+0.15%)	⬆️

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[kubukoz]

Can you add Closes #2288 to the description? It'll close the issue automatically once this is merged.

[ceedubs]

Thanks @nasadorian!

This looks good to me, but I don't think that the tests are hitting the case where the key isn't in the map. Could you explicitly test that case? It could probably be a unit test and/or an sbt-doctest example.

[ceedubs]

LGTM thanks, @nasadorian!