LINUX_PREFERRED_GCC_FORMULA: Bump to gcc@11

[sjackman]

Change LINUX_PREFERRED_GCC_FORMULA from gcc@5 to gcc@11.

Similarly to how we bumped the brewed Glibc version before building bottles with that Glibc version, perhaps we can also bump the preferred brewed GCC version before building bottles with that GCC version.

See #13619 (comment)

I'd like to have a stable release of Homebrew 3.6.0 that migrates our users to glibc 2.35 and gcc@11 before we move our bottling infrastructure to Ubuntu 22.04.

This PR needs to be merged and Homebrew 3.6.0 tagged simultaneously with merging PR Homebrew/homebrew-core#108816

• gcc@5: remove symlinks to lib homebrew-core#108816

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• Update bottling Linux distribution to Ubuntu 22.04 #13619

[BrewTestBot]

Review period will end on 2022-08-25 at 21:11:57 UTC.

[MikeMcQuaid]

I'd like to have a stable release of Homebrew 3.6.0 that migrates our users to glibc 2.35 and gcc@11 before we move our bottling infrastructure to Ubuntu 22.04.

Can you explain why? I have a pretty strong preference to land this Ubuntu 22.04 migration at the same time as we change our CI over (which will all be when 3.6.0 is tagged).

This PR needs to be merged and Homebrew 3.6.0 tagged simultaneously with merging PR Homebrew/homebrew-core#108816

👍🏻

[MikeMcQuaid]

This doesn't feel like the right move to me.

[sjackman]

Closing in favour of PR

• Update LINUX_CI_OS_VERSION to Ubuntu 22.04 #13733