Implement Godot-in-the-loop test suite and fix debugger errors (#788)

Fixes for get variables issues
1. Same reference but different variable override fix, which resulted in variables being lost
** Now different GodotVariable instances are used for different variables with same reference
** const replacement = {value: rawObject, sub_values: sub_values } as GodotVariable;
2. 'Signal' type handling crash and string representation fix
** value.sub_values()?.map
3. Empty scopes return fix
** if (this.ongoing_inspections.length === 0  && stackVars.remaining == 0)
4. Various splice from findIndex fixes (where findIndex can return -1)
5. Added variables tests
**  updated vscode types to version 1.96 to use `onDidChangeActiveStackItem` for breakpoint hit detection in tests
1 & 3 should fix https://github.com/godotengine/godot-vscode-plugin/issues/779

.gitignore

@@ -4,3 +4,5 @@ node_modules
 .vscode-test
 workspace.code-workspace
 .history
+.godot
+*.tmp