fix(about): add missing buildInfo in mocked health response

[tthvo]

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Related to #1303 #1315

Description of the change:

• Updated Mirage API mocks to include git commit hash.
• Fixed Mirage /api/v2/targets API route to consider dryrun query parameter.
• Fixed some remaining type-check issues.

Motivations

Previously, About page is throwing error in preview mode.