Move MoltenVK clean on dependency build from fetchDependencies.sh to package_ext_libs.sh.

Scripts/package_ext_libs.sh

@@ -9,3 +9,7 @@ rm -rf "${MVK_EXT_LIB_DST_OS_PATH}"
 mkdir -p "${MVK_EXT_LIB_DST_OS_PATH}"
 
 cp -a "${MVK_BUILT_PROD_PATH}/"*.a "${MVK_EXT_LIB_DST_OS_PATH}"
+
+# Clean MoltenVK to ensure the next MoltenVK build will use the latest external library versions.
+make --quiet clean
+

fetchDependencies

@@ -260,10 +260,5 @@ xcodebuild 									\
 	${XC_BUILD_VERBOSITY}					\
 	build
 
-echo ========== Cleaning MoltenVK build. Be sure to build MoltenVK again. ==========
-
-make --quiet clean
-
-echo
 echo ========== Done! ==========