Remove some preinstalled packages on CI runner to gain more free space

[Po-Chun-Chien]

CI run ubuntu-latest:z3-static has been failing regularly due to insufficient disk space. This PR removes some unnecessary preinstalled packages from the runner.

Examples of recent failed runs:

• https://github.com/stanford-centaur/smt-switch/actions/runs/18076950461
• https://github.com/stanford-centaur/smt-switch/actions/runs/18076332446
• https://github.com/stanford-centaur/smt-switch/actions/runs/18023317071
• Add support for Floating-Point theory (currently cvc5 only) #428 (comment)

[CyanoKobalamyne]

I think we should try to use the recommended way to uninstall things instead of just deleting files when we can (e.g., ghcup nuke instead of rm -rf /opt/ghc). Also, it turns out that just removing Haskell and the Android SDKs frees up ~17 GB already, so we don't need to do the rest, because that just eats up time. I made these changes in #431, so you can probably close this, unless you want to propose more changes.