Set timeout for E2E tests. (#48381)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/48381

Right now, the E2E tests for RNTester does not have a timeout.
It can happen that the emulator get stuck and the action times out.

The default timeout is 6 hours, which is definitely too much and wasteful, so let's reduce it to 1 hour.

{F1974112110}

## Changelog:
[Internal] - Set timeout for E2E tests to 1 hour

Reviewed By: robhogan, blakef

Differential Revision: D67620423

fbshipit-source-id: c507d1222fca49287fafe6da4bffe559d8687b99