Allow HOMEBREW_PREFIX replacement in external patches #30877

Job	Run time
syntax	40s
vendored gems	50s
tap syntax	6m 51s
formula audit	4m 34s
cask audit	2m 26s
test default formula (Ubuntu 22.04)	1m 32s
tests (online)	5m 19s
test default formula (Ubuntu 20.04)	2m 53s
update-test (Ubuntu 22.04)	22s
tests (generic OS)	2m 59s
test default formula (macOS 13 x86_64)	4m 2s
update-test (macOS)	25s
test default formula (macOS 15 arm64)	1m 19s
tests (Ubuntu 22.04)	3m 11s
tests (Ubuntu 20.04)	3m 44s
tests (macOS 13 x86_64)	11m 31s
tests (macOS 15 arm64)	5m 48s
	58m 26s

Provide feedback