[ML] Anomaly Detection: Fix test to reflect model memory limit change. (#65967)

Adapt jest test mocks to consider update introduced in #65652.
# Conflicts:
#	x-pack/plugins/ml/server/models/job_validation/job_validation.test.ts

Author: walterra

x-pack/plugins/ml/server/models/job_validation/job_validation.test.ts

@@ -14,6 +14,13 @@ const callWithRequest: APICaller = (method: string) => {
     if (method === 'fieldCaps') {
       resolve({ fields: [] });
       return;
+    } else if (method === 'ml.info') {
+      resolve({
+        limits: {
+          effective_max_model_memory_limit: '100MB',
+          max_model_memory_limit: '1GB',
+        },
+      });
     }
     resolve({});
   }) as Promise<any>;