Fix color emission to check for interactive terminal (backport #3334)

[mergify]

This is an automatic backport of pull request #3334 done by Mergify.

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Original PR Body

This is really hard to test. See Release Notes below for user-facing API and limitations.

I would like to test this but it can't be done in ScalaTest nor really even with SBT, you need to publishLocal and then use scala-cli and then some way of processing the output for correctness.

Contributor Checklist

• Did you add Scaladoc to every public function/method?
• Did you add at least one test demonstrating the PR?
• Did you delete any extraneous printlns/debugging code?
• Did you specify the type of improvement?
• Did you add appropriate documentation in docs/src?
• Did you request a desired merge strategy?
• Did you add text to be included in the Release Notes for this change?

Type of Improvement

• Feature (or new API)

Desired Merge Strategy

• Squash

Release Notes

• Chisel will now detect when it should print warnings, errors, and deprecations in color.
  • Color can be controlled with environment variable CHISEL_USE_COLOR. Set to true to force Chisel to use color and false to disable it.
  • Due to how the JVM works, detection requires interactive stdout, stderr, and stdin. Build tools like SBT virtualize stdin and thus color will be disabled by default when running a Chisel main with SBT. Detection also requires environment variable TERM to be set to something other than dumb.

Reviewer Checklist (only modified by reviewer)

• Did you add the appropriate labels? (Select the most appropriate one based on the "Type of Improvement")
• Did you mark the proper milestone (Bug fix: 3.5.x or 3.6.x depending on impact, API modification or big change: 5.0.0)?
• Did you review?
• Did you check whether all relevant Contributor checkboxes have been checked?
• Did you do one of the following when ready to merge:
  • Squash: You/ the contributor Enable auto-merge (squash), clean up the commit message, and label with Please Merge.
  • Merge: Ensure that contributor has cleaned up their commit history, then merge with Create a merge commit.