Fix doc examples for Ior.map

[ybasket]

Ior.map had just the copy&pasted examples from Ior.bimap, this PR replaces them with proper, equivalent examples for map.

[codecov-io]

Codecov Report

Merging #3314 into master will increase coverage by 0.21%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #3314      +/-   ##
==========================================
+ Coverage    93.2%   93.41%   +0.21%     
==========================================
  Files         377      378       +1     
  Lines        7604     7629      +25     
  Branches      199      222      +23     
==========================================
+ Hits         7087     7127      +40     
+ Misses        517      502      -15

Flag	Coverage Δ
#scala_version_212	93.49% <ø> (?)
#scala_version_213	93.2% <ø> (ø)	⬆️

Impacted Files	Coverage Δ
core/src/main/scala/cats/data/Ior.scala	98.52% <ø> (+0.03%)	⬆️
core/src/main/scala/cats/Show.scala	100% <0%> (ø)	⬆️
core/src/main/scala/cats/instances/tuple.scala	100% <0%> (ø)	⬆️
core/src/main/scala/cats/data/Const.scala	100% <0%> (ø)	⬆️
core/src/main/scala/cats/data/Validated.scala	100% <0%> (ø)	⬆️
...cala-2.12/cats/kernel/compat/TraversableOnce.scala	0% <0%> (ø)
core/src/main/scala/cats/data/NonEmptyList.scala	98.73% <0%> (+0.01%)	⬆️
core/src/main/scala/cats/data/NonEmptyVector.scala	99.25% <0%> (+0.01%)	⬆️
core/src/main/scala/cats/data/NonEmptySet.scala	97.64% <0%> (+0.02%)	⬆️
core/src/main/scala/cats/instances/option.scala	98.3% <0%> (+0.02%)	⬆️
... and 10 more

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[LukaJCB]

Thank you!

[travisbrown]

Thanks for catching this!