skip flaky suite (#70764)

packages/kbn-optimizer/src/integration_tests/basic_optimization.test.ts

@@ -168,7 +168,8 @@ it.skip('builds expected bundles, saves bundle counts to metadata', async () =>
   `);
 });
 
-it('uses cache on second run and exist cleanly', async () => {
+// FLAKY: https://github.com/elastic/kibana/issues/70764
+it.skip('uses cache on second run and exist cleanly', async () => {
   const config = OptimizerConfig.create({
     repoRoot: MOCK_REPO_DIR,
     pluginScanDirs: [Path.resolve(MOCK_REPO_DIR, 'plugins')],