kew: update formula to add macOS compatibility

[ravachol]

Removes unnecessary dependencies on Linux, FreeImage and FFmpeg.

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[bevanjkay]

Tests failed on all MacOS versions;

==> Testing kew
  ==> /opt/homebrew/Cellar/kew/3.0.0/bin/kew path /private/tmp/kew-test-20241030-24137-dt5plz
  mkdir: No such file or directory
  Error: kew: failed
  An exception occurred within a child process:
    BuildError: Failed executing: /opt/homebrew/Cellar/kew/3.0.0/bin/kew path /private/tmp/kew-test-20241030-24137-dt5plz