fix (cherry-pick): get supportedChains to avoid blocking the confirmation process

[vinistevam]

Description

Cherry-pick of #28313 for release 12.7.0.

Related issues

Fixes: #28255 #28257

Manual testing steps

1. Use a proxy to intercept requests
2. Start a Send flow
3. Intercept the request to security-alerts.api.cx.metamask.io
4. See send flow cannot be initiated until we have a response to this request

Screenshots/Recordings

Before

After

supported-chains-.webm

unsupported-chains.webm

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.

[metamaskbot]

Builds ready [3b9d84c]

• 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, 10, 11, 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 (1893 ± 94 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	324	2375	1747	511	245
		domContentLoaded	1639	2324	1868	181	87
		load	1647	2375	1893	195	94
		domInteractive	21	89	53	19	9
		backgroundConnect	7	103	22	21	10
		firstReactRender	48	118	84	25	12
		getState	4	48	16	16	8
		initialActions	0	1	0	0	0
		loadScripts	1177	1739	1382	149	72
		setupStore	11	79	36	25	12
		uiStartup	1861	2580	2103	203	98

Bundle size diffs [🚨 Warning! Bundle size has increased!]

• background: 860 Bytes (0.02%)
• ui: 2.42 KiB (0.03%)
• common: 776 Bytes (0.01%)