Add --dump-fir option to ChiselStage (backport #3453)

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This is an automatic backport of pull request #3453 done by Mergify.
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Changes to be committed:
	modified:   src/main/scala/circt/stage/Annotations.scala
	modified:   src/main/scala/circt/stage/package.scala
	modified:   src/test/scala/circtTests/stage/ChiselStageSpec.scala

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   src/main/scala/circt/stage/CIRCTOptions.scala
	both modified:   src/main/scala/circt/stage/ChiselStage.scala
	both modified:   src/main/scala/circt/stage/phases/CIRCT.scala

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Original PR Body

As usual, a 20 min hack had a bit of scope creep but I think this is a nice improvement

I'm open to a better name for the argument, but I think the functionality is pretty handy

@fabianschuiki FYI

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

• Rebase

Release Notes

This option will dump the .fir before invoking firtool.

• Additional changes:
  • Use os.lib for invoking firtool
  • Use lazy serialization to avoid holding the entire FIRRTL in memory.
  • Mix NoStackTrace into FirtoolNotFound
  • Fix detection of no firtool

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, 3.6.x, or 5.x depending on impact, API modification or big change: 6.0)?
• 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.