Update docs and code for remaining references to 'custom bundle' #11066

Job	Run time
build_node (ubuntu-latest)	1m 15s
build_node (macos-latest)	1m 25s
build_node (windows-latest)	5m 38s
lint_node	42s
Ruby 3.1 on ubuntu-latest	16m 27s
lint_ruby	19s
Ruby 3.2 on ubuntu-latest	14m 21s
Ruby 3.3 on ubuntu-latest	9m 57s
Verify Jekyll website builds	12s
Ruby 3.1 on macos-latest	9m 12s
Ruby 3.2 on macos-latest	8m 52s
Ruby 3.3 on macos-latest	7m 15s
Ruby 3.1 on windows-latest	21m 39s
Ruby 3.2 on windows-latest	19m 15s
Ruby 3.3 on windows-latest	23m 19s
	2h 19m 48s

Provide feedback