fix: postgres test fail

Author: Moumouls

spec/ParseGraphQLServer.spec.js

@@ -105,7 +105,10 @@ describe('ParseGraphQLServer', () => {
       const server2 = await parseGraphQLServer._getServer();
       expect(server1).toBe(server2);
 
-      parseGraphQLServer.parseGraphQLSchema.schemaCache.clear();
+      // Trigger a schema change
+      const obj = new Parse.Object('SomeClass');
+      await obj.save();
+
       const server3 = await parseGraphQLServer._getServer();
       const server4 = await parseGraphQLServer._getServer();
       expect(server3).not.toBe(server2);