selenium-server-standalone: fix plist jar location

The jar file is installed into libexec, which is not reflected in the plist definition.

Closes #27712.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
lilypond 2.18.2

Closes #27720.

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