Switch to our fork of art

The change needed for infra has been already merged.

Change-Id: I709d5cd3afde14388fa0a7eedb0e14d76965f51e

default.xml

@@ -34,7 +34,7 @@
     <linkfile src="root.bp" dest="Android.bp" />
     <linkfile src="bootstrap.bash" dest="bootstrap.bash" />
   </project>
-  <project path="art" name="platform/art" groups="pdk" remote="aosp" />
+  <project path="art" name="LineageOS/android_art" groups="pdk" />
   <project path="bionic" name="LineageOS/android_bionic" groups="pdk" />
   <project path="bootable/recovery" name="LineageOS/android_bootable_recovery" groups="pdk" />
   <project path="compatibility/cdd" name="platform/compatibility/cdd" groups="pdk" remote="aosp" />