Remove unreferenced message.app-image-dir-does-not-exist and message.app-image-dir-does-not-exist.advice keys

Author: alexeysemenyukoracle

src/jdk.jpackage/macosx/classes/jdk/jpackage/internal/resources/MacResources.properties

@@ -72,8 +72,6 @@ message.ignoring.symlink=Warning: codesign is skipping the symlink {0}.
 message.already.signed=File already signed: {0}.
 message.keychain.error=Error: unable to get keychain list.
 message.building-bundle=Building Mac App Store Package for {0}.
-message.app-image-dir-does-not-exist=Specified application image directory {0}: {1} does not exists.
-message.app-image-dir-does-not-exist.advice=Confirm that the value for {0} exists.
 message.invalid-identifier=invalid mac bundle identifier [{0}].
 message.invalid-identifier.advice=specify identifier with "--mac-package-identifier".
 message.building-dmg=Building DMG package for {0}.