chore(gitignore): add playaround area of pacakge path

.gitignore

 # collected from https://github.com/github/gitignore/tree/master/Global
 
+# ignore certain package pathes, dedicated for local playaround classes not to be committed
+src/main/java/test/
+
 # maven
 target/
 
@@ -82,4 +85,4 @@ local.properties
 # Scala IDE specific (Scala & Java development for Eclipse)
 .cache-main
 .scala_dependencies
-.worksheet
+.worksheet
\ No newline at end of file