fix(integ-runner): don't throw error if tests pass (#20511)

If you run `integ-runner --update-on-failed` and the test succeeds, then
the cli should not return an exit code.

re #20384


----

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packages/@aws-cdk/integ-runner/lib/cli.ts

@@ -49,9 +49,10 @@ async function main() {
 
  let failedSnapshots: IntegTestWorkerConfig[] = [];
  if (argv['max-workers'] < testRegions.length * (profiles ?? [1]).length) {
- logger.warning('You are attempting to run %s tests in parallel, but only have %s workers. Not all of your profiles+regions will be utilized', argv.profiles*argv['parallel-regions'], argv['max-workers']);
+ logger.warning('You are attempting to run %s tests in parallel, but only have %s workers. Not all of your profiles+regions will be utilized', argv.profiles * argv['parallel-regions'], argv['max-workers']);
  }
 
+ let testsSucceeded = false;
  try {
  if (argv.list) {
  const tests = await new IntegrationTests(argv.directory).fromCliArgs();
@@ -99,6 +100,8 @@ async function main() {
  verbose: argv.verbose,
  updateWorkflow: !argv['disable-update-workflow'],
  });
+ testsSucceeded = success;
+
 
  if (argv.clean === false) {
  logger.warning('Not cleaning up stacks since "--no-clean" was used');
@@ -125,7 +128,9 @@ async function main() {
  if (!runUpdateOnFailed) {
  message = 'To re-run failed tests run: yarn integ-runner --update-on-failed';
  }
- throw new Error(`Some snapshot tests failed!\n${message}`);
+ if (!testsSucceeded) {
+ throw new Error(`Some tests failed!\n${message}`);
+ }
  }
 
 }