Upgrade Micronaut to 2.0.0.RC1

[alvarosanchez]

• Have you followed the guidelines for contributing?
• Have you checked that there aren't other open pull requests for the same formula update/change?
• Have you built your formula locally with brew install --build-from-source <formula>, where <formula> is the name of the formula you're submitting?
• Is your test running fine brew test <formula>, where <formula> is the name of the formula you're submitting?
• Does your build pass brew audit --strict <formula> (after doing brew install <formula>)?

---

This PR upgrades Micronaut to the new 2.x binary packages. Compiled from source as requested in #56440

brew audit --strict fails because v2.0.0.RC1 is a GitHub prerelease. However, there is no 2.x release (yet).

Hopefully this is ready to be merged 🙏

[SMillerDev]

https://docs.brew.sh/Acceptable-Formulae#stable-versions states that versions must be stable to be accepted. I think we need to wait until 2.0 is actually released for this.

[alvarosanchez]

Ok, will update this PR when 2.0.0 is out.

Other than that, are there any other changes required or does the formula look good?