Fixes the default configuration for snapId, by adding the missing npm: prefix

Explanation

GatorPermissionsController provides a default value for permissionsProviderSnapId, but previously this incorrectly omitted the npm: prefix.

This change adds the prefix.

Changelog:

Corrects the default Permissions Provider SnapId configuration value for the GatorPermissionsController which was previously missing the npm: prefix.

Checklist

• I've updated the test suite for new or updated code as appropriate
• N/A I've updated documentation (JSDoc, Markdown, etc.) for new or updated code as appropriate
• N/A I've communicated my changes to consumers by updating changelogs for packages I've changed, highlighting breaking changes as necessary
• N/A I've prepared draft pull requests for clients and consumer packages to resolve any breaking changes