bottle: improve relocatable debugging.

* When Homebrew developer mode is enabled, if a bottle is not found to
  be relocatable attempt to explain why
* Print out paths of each file that still contains the string search for
* If the string searched for was found in an executable, check to see
  if `otool` can explain the string's appearance
* If otool can't explain, see if `strings` can explain

Closes #23824.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>