[Toolchain] Fix Compatibility version

Author: shahmishal

utils/build-script-impl

@@ -2564,7 +2564,7 @@ if [[ "${INSTALLABLE_PACKAGE}" ]] ; then
       DARWIN_TOOLCHAIN_INSTALL_LOCATION="/Library/Developer/Toolchains/${DARWIN_TOOLCHAIN_NAME}.xctoolchain"
       DARWIN_TOOLCHAIN_INFO_PLIST="${INSTALL_DESTDIR}/${TOOLCHAIN_PREFIX}/Info.plist"
       DARWIN_TOOLCHAIN_REPORT_URL="https://bugs.swift.org/"
-      COMPATIBILITY_VERSION=2
+      COMPATIBILITY_VERSION=1
       DARWIN_TOOLCHAIN_CREATED_DATE="$(date -u +'%a %b %d %T GMT %Y')"
 
       echo "-- Removing: ${DARWIN_TOOLCHAIN_INFO_PLIST}"