release planning: v1.18.0

[flavorjones]

See milestone at https://github.com/sparklemotion/nokogiri/milestone/32

Keeping the scope of this release pretty small because time is tight.

• drop Ruby 3.0, add Ruby 3.4 - drop support for Ruby 3.0, add support for Ruby 3.4 #3273
  • drop Ruby 3.0
    • dep: drop Ruby 3.0 #3368
  • Drop 32-bit platforms from the set of native precompiled gems. #3369
    • ext: stop precompiling native gems for x86-linux and x86-mingw32 #3374
  • add Ruby 3.4
    • ci: generate a generic linux snapshot image rake-compiler/rake-compiler-dock#130
    • release rake-compiler-dock 1.6.0 dropping manylinux
    • use rcd 1.6.0 and ship musl native gems - ext: update to rake-compiler-dock v1.6.0, ship both GNU and Musl native gems #3375
    • revert musl compat hacks - ext: revert hacks for GNU/Musl compatibility #3384
    • release rake-compiler-dock 1.7.0 adding ruby 3.4
      • Add Ruby 3.4 cross-compilation support. rake-compiler/rake-compiler-dock#131
    • ext: add Ruby 3.4 to the precompiled native gems #3376
• focus on performance improvements
  • [perf] Explore re-using XPathContext objects, and compiling XPath expressions #3266
    • perf(cruby): reuse XPathContext objects #3378
  • go through other candidates
    • not going to add any more scope at this time
• remaining hack day / kwarg PRs and methods
  • decided not to do this in 1.18

[flavorjones]

Released v1.8.0.rc1: https://github.com/sparklemotion/nokogiri/releases/tag/v1.18.0.rc1