fix uncaught exceptions from CustomSpokenForms.updateSpokenFormMaps (#2261) (#2283)

fixes #2261

## Checklist

- [-] I have added
[tests](https://www.cursorless.org/docs/contributing/test-case-recorder/)
- [-] I have updated the
[docs](https://github.com/cursorless-dev/cursorless/tree/main/docs) and
[cheatsheet](https://github.com/cursorless-dev/cursorless/tree/main/cursorless-talon/src/cheatsheet)
- [-] I have not broken the cheatsheet

Author: pokey

packages/cursorless-engine/src/spokenForms/CustomSpokenForms.ts

@@ -57,10 +57,11 @@ export class CustomSpokenForms {
 
   constructor(private talonSpokenForms: TalonSpokenForms) {
     this.disposable = talonSpokenForms.onDidChange(() =>
-      this.updateSpokenFormMaps(),
+      this.updateSpokenFormMaps().catch(() => {}),
     );
 
     this.customSpokenFormsInitialized = this.updateSpokenFormMaps();
+    this.customSpokenFormsInitialized.catch(() => {});
   }
 
   /**