fix(e2e): guard handshake test teardown when app init fails

Use optional chaining on app?.teardown() and thisApp?.teardown() to
prevent cascading TypeError when beforeAll fails before assigning app.

Author: jacekradko

integration/tests/handshake.test.ts

@@ -1076,7 +1076,7 @@ test.describe('Client handshake with organization activation @nextjs', () => {
   });
 
   test.afterAll('setup local Clerk API mock', async () => {
-    await app.teardown();
+    await app?.teardown();
     return new Promise<void>(resolve => jwksServer.close(() => resolve()));
   });
 
@@ -1460,7 +1460,7 @@ test.describe('Client handshake with an organization activation avoids infinite
   });
 
   test.afterAll('setup local Clerk API mock', async () => {
-    await thisApp.teardown();
+    await thisApp?.teardown();
     return new Promise<void>(resolve => jwksServer.close(() => resolve()));
   });