make message clearer

Signed-off-by: Juan Pablo Garcia Ripa <sarabadu@gmail.com>

plugins/scaffolder-backend/src/scaffolder/tasks/NunjucksWorkflowRunner.test.ts

@@ -1005,7 +1005,7 @@ describe('NunjucksWorkflowRunner', () => {
         parameters: {},
       });
       await expect(runner.execute(task)).rejects.toThrow(
-        'Invalid each value passed to action jest-validated-action, "${{parameters.data}}" cannot be resolved to a value',
+        'Invalid value on action jest-validated-action.each parameter, "${{parameters.data}}" cannot be resolved to a value',
       );
       expect(fakeActionHandler).not.toHaveBeenCalled();
     });

plugins/scaffolder-backend/src/scaffolder/tasks/NunjucksWorkflowRunner.ts

@@ -310,7 +310,7 @@ export class NunjucksWorkflowRunner implements WorkflowRunner {
 
       if (step.each && !resolvedEach) {
         throw new InputError(
-          `Invalid each value passed to action ${action.id}, "${step.each}" cannot be resolved to a value`,
+          `Invalid value on action ${action.id}.each parameter, "${step.each}" cannot be resolved to a value`,
         );
       }