refactor: remove whats new notification for staking

[jclancy93]

Description

Removes what's new notification for direct staking within MetaMask. This notification is being removed because it has been there for some time now and our team has been asked to remove it by May 9th

Related issues

Fixes: STAKE-689

Manual testing steps

1. Install or update extension
2. View what's new modal
3. Confirm that staking notification is no longer there

Screenshots/Recordings

Before

https://www.loom.com/share/bd5aee8a123e4e1c8d76bbd89a22c32b

After

https://www.loom.com/share/73c1e2924271431c8a98c8aed07da4dc

Pre-merge author checklist

• [x] I’ve followed MetaMask Coding Standards.
• [x] 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
• [x] I’ve applied the right labels on the PR (see labeling guidelines). Not required for external contributors.

Pre-merge reviewer checklist

• [x] I've manually tested the PR (e.g. pull and build branch, run the app, test code being changed).
• [x] 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[bot]]

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.

[jclancy93]

I have read the CLA Document and I hereby sign the CLA

[metamaskbot]

Builds ready [2193955]

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

Page Load Metrics (1524 ± 772 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	65	225	120	41	20
		domContentLoaded	10	68	22	15	7
		load	51	4020	1524	1608	772
		domInteractive	10	68	22	15	7

Bundle size diffs [🚀 Bundle size reduced!]

• background: 0 Bytes (0.00%)
• ui: -151 Bytes (-0.00%)
• common: -1.05 KiB (-0.02%)