fix: replace unreliable setTimeout usage with waitFor

[Matt561]

Description

This PR aims to improve a flaky test for the add-contact component.

Related issues

Fixes:

Manual testing steps

1. Run the test locally

Screenshots/Recordings

Before

N/A

After

N/A

Pre-merge author checklist

• I've followed MetaMask Contributor Docs and MetaMask Extension Coding Standards.
• I've completed the PR template to the best of my ability
• I’ve included tests if applicable
• I’ve documented my code using JSDoc format if applicable
• I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Pre-merge reviewer checklist

• I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• I confirm that this PR addresses all acceptance criteria described in the ticket it closes and includes the necessary testing evidence such as recordings and or screenshots.

[github-actions]

CLA Signature Action: All authors have signed the CLA. You may need to manually re-run the blocking PR check if it doesn't pass in a few minutes.

[Gudahtt]

LGTM, great catch!

[cryptotavares]

Nice catch.. left a really minor comment.

[cryptotavares]

You can findBy* queries here and avoid using the waitFor.

[metamaskbot]

Builds ready [95041d4]

• builds: chrome, firefox
• builds (beta): chrome
• builds (flask): chrome, firefox
• builds (MMI): chrome, firefox
• builds (test): chrome, firefox
• builds (test-flask): chrome, firefox
• build viz: Build System
• mv3: Background Module Init Stats
• mv3: UI Init Stats
• mv3: Module Load Stats
• mv3: Bundle Size Stats
• mv2: E2e Actions Stats
• code coverage: Report
• storybook: Storybook
• typescript migration: Dashboard
• all artifacts
• bundle viz:

  • background: 0, 1, 2, 3, 4, 5, 6, 7
  • common: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9
  • content-script: 0
  • offscreen: 0
  • ui: 0, 1, 10, 11, 12, 2, 3, 4, 5, 6, 7, 8, 9

Page Load Metrics (1782 ± 69 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	1608	2268	1785	138	66
		domContentLoaded	1591	2158	1746	129	62
		load	1600	2263	1782	144	69
		domInteractive	26	174	47	32	16
		backgroundConnect	8	106	35	28	13
		firstReactRender	48	370	133	70	34
		getState	5	63	14	16	8
		initialActions	0	1	0	0	0
		loadScripts	1145	1583	1291	102	49
		setupStore	5	67	16	19	9
		uiStartup	1774	2767	2060	231	111

Bundle size diffs

• background: 0 Bytes (0.00%)
• ui: 0 Bytes (0.00%)
• common: 0 Bytes (0.00%)