Add declare to class fields in child class that overrides a base clas… (#2673)

…s field without explicitly reinitializing the field

According to an internal Google audit of TS code: When public class
fields are enabled and target output is set to ES2022, TypeScript
reports the following error -

```
class A {
    x: SomeType = new SomeType();
}

class B extends A {

    override x!: NarrowType;      // Property 'x' will overwrite the base property in 'A'. If this is intentional, add an initializer. Otherwise, add a 'declare' modifier or remove the redundant declaration.

}
```

---------

Co-authored-by: pre-commit-ci-lite[bot] <117423508+pre-commit-ci-lite[bot]@users.noreply.github.com>

Author: bjaspan

packages/cursorless-vscode/src/ScopeTreeProvider.ts

@@ -212,7 +212,7 @@ function getSupportCategories(): SupportCategoryTreeItem[] {
 }
 
 class ScopeSupportTreeItem extends TreeItem {
-  public readonly label!: TreeItemLabel;
+  public declare readonly label: TreeItemLabel;
 
   /**
    * @param scopeTypeInfo The scope type info