ecl 13.5.1

Closes #21775.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
selenium-server-standalone 2.34

Closes #21776.

Signed-off-by: Adam Vandenberg <flangy@gmail.com>
grads: point to documentation in caveats
Add helper to HOMEBREW_PREFIX

Add standard? to HOMEBREW_PREFIX for testing that Homebrew installed
to /usr/local
Use standard? internally
luarocks: use helper
mlkit: use helper
mlton: use helper