chore(bulk-model-sync-gradle): use wildcards in git ignore

Author: mhuster23

bulk-model-sync-gradle-test/.gitignore

@@ -40,10 +40,7 @@ bin/
 
 ### Mac OS ###
 .DS_Store
-/test-repo/languages/GraphLang/classes_gen/
-/test-repo/languages/GraphLang/generator/
-/test-repo/languages/GraphLang/source_gen/
-/test-repo/languages/GraphLang/source_gen.caches/
-/test-repo/solutions/GraphSolution/source_gen/
-/test-repo/solutions/GraphSolution/classes_gen/
-/test-repo/solutions/GraphSolution/source_gen.caches/
+/test-repo/**/**/classes_gen/
+/test-repo/**/**/generator/
+/test-repo/**/**/source_gen/
+/test-repo/**/**/source_gen.caches/