fix(reportextractor): Ensure simple-configuration can discover app identity

Author: akash1810

cdk/lib/__snapshots__/report.test.ts.snap

@@ -718,8 +718,11 @@ exports[`The Report stack matches the snapshot for CODE 1`] = `
         "Environment": {
           "Variables": {
             "APP": "reportextractor",
+            "App": "reportextractor",
             "STACK": "mobile-notifications",
             "STAGE": "CODE",
+            "Stack": "mobile-notifications",
+            "Stage": "CODE",
           },
         },
         "Handler": "com.gu.notifications.extractor.Lambda",
@@ -1980,8 +1983,11 @@ exports[`The Report stack matches the snapshot for PROD 1`] = `
         "Environment": {
           "Variables": {
             "APP": "reportextractor",
+            "App": "reportextractor",
             "STACK": "mobile-notifications",
             "STAGE": "PROD",
+            "Stack": "mobile-notifications",
+            "Stage": "PROD",
           },
         },
         "Handler": "com.gu.notifications.extractor.Lambda",

cdk/lib/report.ts

@@ -125,6 +125,13 @@ export class Report extends GuStack {
 			timeout: Duration.minutes(1),
 			monitoringConfiguration: { noMonitoring: true },
 			loggingFormat: LoggingFormat.TEXT,
+
+			// Although GuCDK provides UPPERCASED env vars for stack, stage, app, simple-configuration reads Title cased env vars.
+			environment: {
+				Stack: stack,
+				Stage: stage,
+				App: reportExtractorApp,
+			},
 		});
 
 		reportExtractor.addToRolePolicy(