docs: update context bridge docs about Promises and Errors (#32533)
docs: update context bridge docs about Promises and Errors (#32533)

* Update context bridge docs about Promises

From my testing it doesn't remove Promises in nested objects,
also according to the test suite it does not:
https://github.com/electron/electron/blob/80577a4f08824c031ad020b8f4e3c5975ff8081a/spec-main/api-context-bridge-spec.ts#L693

* docs: Update docs for errors too
electron/electron,electron/electron,gerhardberger/electron,electron/electron,gerhardberger/electron,electron/electron,gerhardberger/electron,gerhardberger/electron,electron/electron,gerhardberger/electron,gerhardberger/electron,electron/electron,gerhardberger/electron,electron/electron