chore: make security optional for /edge/validate endpoint (#5739)

We've had a couple of misunderstandings from people surprised that
Unleash allows posts against the `/edge/validate` endpoint without an
API key. It is intentional that this endpoint does not require an
Authorization header, so this PR updates our OpenAPI spec to clarify
that there is no security required for `/edge/validate`

src/lib/routes/edge-api/index.ts

@@ -63,6 +63,7 @@ export default class EdgeController extends Controller {
             middleware: [
                 this.openApiService.validPath({
                     tags: ['Edge'],
+                    security: [{}],
                     summary: 'Check which tokens are valid',
                     description:
                         'This operation accepts a list of tokens to validate. Unleash will validate each token you provide. For each valid token you provide, Unleash will return the token along with its type and which projects it has access to.',