add VSCode user debug settings to git ignore list (#2967)

VSCode uses a `.vscode/launch.json` file for configuring the debugger.
This PR adds a line to the `.gitignore` file to also ignore it along
with the already-ignored `.vscode/settings.json` file.

---------

Co-authored-by: jonmeow <jperkins@google.com>

.gitignore

@@ -8,8 +8,9 @@
 # Directories created by python.
 **/__pycache__/
 
-# Ignore the user's VSCode settings.
+# Ignore the user's VSCode settings and debug setup.
 /.vscode/settings.json
+/.vscode/launch.json
 
 # Ignore the user's Idea settings.
 /.idea/