CMake: Force adhoc signing

Now that VST3 builds are signed before and after manifest generation, it
may be necessary to force-sign in order to overwrite the
previously-applied signature.

extras/Build/CMake/checkBundleSigning.cmake

@@ -33,5 +33,5 @@ execute_process(
 
 if(result)
     message(STATUS "Replacing invalid signature with ad-hoc signature")
-    execute_process(COMMAND "${JUCE_XCRUN}" codesign -s - "${src}")
+    execute_process(COMMAND "${JUCE_XCRUN}" codesign -f -s - "${src}")
 endif()