ignoring venv in .gitignore

(cherry picked from commit 92dd34ae968a48c35a34e778550577a1d6d86205)

.gitignore

@@ -191,3 +191,7 @@ godot.creator.*
 
 # compile commands (https://clang.llvm.org/docs/JSONCompilationDatabase.html)
 compile_commands.json
+
+# Python development
+.venv
+venv