fix: config validation

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## Related Issues


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packages/spacecat-shared-data-access/src/models/site/config.js

@@ -18,11 +18,11 @@ export const configSchema = Joi.object({
     channel: Joi.string(),
   }),
   alerts: Joi.array().items(Joi.object({
-    type: Joi.string(),
+    type: Joi.string().required(),
     byOrg: Joi.boolean(),
     mentions: Joi.array().items(Joi.object({ slack: Joi.array().items(Joi.string()) })),
-  })),
-});
+  }).unknown(true)),
+}).unknown(true);
 
 export const DEFAULT_CONFIG = {
   slack: {

packages/spacecat-shared-data-access/test/it/generateSampleData.js

@@ -180,6 +180,10 @@ export default async function generateSampleData(
           type: '404',
           byOrg: true,
           mentions: [{ slack: [`${i}-slackId`] }],
+        },
+        {
+          type: 'organic-keywords',
+          country: 'RO',
         }],
       },
     });