[GR-20549] Release 19.3.1.

Author: ezzarghili

mx.graalpython/suite.py

@@ -10,7 +10,7 @@
     "versionConflictResolution": "latest",
 
     "version": "19.3.1",
-    "release": False,
+    "release" : True,
     "groupId": "org.graalvm.graalpython",
     "url": "http://www.graalvm.org/",