Use JDK 23 for builds

[ascopes]

No description provided.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 87.76%. Comparing base (b97acb2) to head (3fa1796).
Report is 6 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #401   +/-   ##
=======================================
  Coverage   87.76%   87.76%           
=======================================
  Files          33       33           
  Lines        1119     1119           
  Branches       74       74           
=======================================
  Hits          982      982           
  Misses        103      103           
  Partials       34       34           

Files with missing lines	Coverage Δ
...protobufmavenplugin/mojo/AbstractGenerateMojo.java	100.00% <ø> (ø)

[ascopes]

Need to enable -proc:full on JDK 23. Looks like they've backported it to the latest JDK releases of Java 17 and Java 11 but not others so may have to use a custom Maven profile for this.