Bug 1965387 - Add features in NimbusTestUtils.setupTest r=nimbus-reviewers,relud

Differential Revision: https://phabricator.services.mozilla.com/D248560

toolkit/components/nimbus/test/NimbusTestUtils.sys.mjs

@@ -726,9 +726,15 @@ export const NimbusTestUtils = {
     experiments,
     secureExperiments,
     clearTelemetry = false,
+    features,
   } = {}) {
     const sandbox = lazy.sinon.createSandbox();
 
+    let cleanupFeatures = null;
+    if (Array.isArray(features)) {
+      cleanupFeatures = NimbusTestUtils.addTestFeatures(...features);
+    }
+
     const store = NimbusTestUtils.stubs.store(storePath);
     const manager = NimbusTestUtils.stubs.manager(store);
     const loader = NimbusTestUtils.stubs.rsLoader(manager);
@@ -751,6 +757,10 @@ export const NimbusTestUtils = {
         ExperimentAPI._resetForTests();
         sandbox.restore();
 
+        if (cleanupFeatures) {
+          cleanupFeatures();
+        }
+
         if (clearTelemetry) {
           Services.fog.testResetFOG();
           Services.telemetry.clearEvents();