FieldConfig: Apply Thresholds for string values (#27656)

* apply thresholds for strings

* apply thresholds for all FieldTypes

packages/grafana-ui/src/utils/standardEditors.tsx

@@ -146,7 +146,7 @@ export const getStandardFieldConfigs = () => {
         { value: 80, color: 'red' },
         { value: 80, color: 'red' },
       ],
       ],
     },
     },
-    shouldApply: field => field.type === FieldType.number,
+    shouldApply: () => true,
     category: ['Thresholds'],
     category: ['Thresholds'],
     getItemsCount: value => (value ? value.steps.length : 0),
     getItemsCount: value => (value ? value.steps.length : 0),
   };
   };