Transformers: Add template variable substitution (#44486)

* Transformers: Add template variable replacement to transformer operator

* Transformers: Add template variable replacement to calculateField transformer

* Transformers: Add scopedVars to transformer template replacement

* Transformers: Add calculateField template variable test

* Transformers: Fix 'undefined' is not assignable to type 'string'

* Transformers: Fix lint-frontend bug

* Fix lint check

* Fix lint

public/app/features/query/state/PanelQueryRunner.ts

@@ -183,6 +183,13 @@ export class PanelQueryRunner {
             return of(data);
           }
 
+          const replace = (option: string): string => {
+            return getTemplateSrv().replace(option, data?.request?.scopedVars);
+          };
+          transformations.forEach((transform: any) => {
+            transform.replace = replace;
+          });
+
           return transformDataFrame(transformations, data.series).pipe(map((series) => ({ ...data, series })));
         })
       );