[FLASK] Fix crash when uninstalling snap

[FrederikBolding]

Explanation

Fixes a crash that would happen when uninstalling a snap from the settings page.

Manual Testing Steps

1. Install any snap.
2. Visit its settings page
3. Uninstall the snap
4. Verify that MM has not crashed

[metamaskbot]

Builds ready [a5eb7f1]

• builds: chrome, firefox, opera
• builds (beta): chrome, firefox, opera
• builds (flask): chrome, firefox, opera
• 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
  • content-script: 0
  • contentscript: contentscript
  • disable-console: disable-console
  • inpage: inpage
  • policy-load: policy-load
  • sentry-install: sentry-install
  • ui: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9

Page Load Metrics (1767 ± 69 ms)

Platform	Page	Metric	Min (ms)	Max (ms)	Average (ms)	StandardDeviation (ms)	MarginOfError (ms)
Chrome	Home	firstPaint	100	255	129	34	16
		domContentLoaded	1592	2223	1746	137	66
		load	1592	2223	1767	144	69
		domInteractive	1592	2223	1746	137	66

highlights:

storybook

• ui/pages/settings/settings.stories.js