update compat to Colors v0.10

[bjarthur]

tests pass locally for me. @kimikage

does this fix #1368 ?

[codecov-io]

Codecov Report

Merging #1383 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1383   +/-   ##
=======================================
  Coverage   90.57%   90.57%           
=======================================
  Files          39       39           
  Lines        3988     3988           
=======================================
  Hits         3612     3612           
  Misses        376      376

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[kimikage]

I guess that the cause of UndefVarError: @colorant_str not defined is a failure of package compilation. Since I don't fully understand the cause of the compilation error (i.e. since reproduction codes are not shown), I cannot say for certain. I think the issue #1368 was already fixed by PR #1377.
However, this PR definitely improves the situation. If this doesn't solve the issue #1368 then there should be something else.