tip for rerunning failed tests

src/content/tips/rerun-failed-tests.md

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+---
+kind: circleci
+title: Rerun only the failed tests when you hit flaky test failures
+description: Save time and money by avoiding rerunning tests that already passed when you hit flaky test failures
+contributor: https://github.com/sebastian-lerner
+snippet: |
+  version: 2.1
+  jobs:
+    test:
+      docker:
+        - image: cimg/python:3.11.0
+      parallelism: 4
+      steps:
+        - checkout
+        - python/install-packages:
+            pkg-manager: pip
+        - run:
+          command: |
+            mkdir test-results
+            TEST_FILES=$(circleci tests glob "**/test_*.py")
+            echo "$TEST_FILES" | circleci tests run --command="xargs pytest -o junit_family=legacy --junitxml=test-results/junit.xml" --verbose --split-by=timings #--split-by=timings optional
+        - store_test_results:
+            path: test-results
+---
+
+If your test suite is prone to flaky test failures, you are probably wasting time and money re-running the entire test suite just to get to a passing build.  CircleCI lets you cut down on that wasted time/money by only re-running the tessts that failed when you hit flaky test failures.  No need to rerun the tests that passed.
+
+The snippet above shows an example using Python & `pytest`, but you can use this functionality with almost any framaework/test runner.  See the [official CircleCI documentation on rerunning only the failed tests](https://circleci.com/docs/use-the-circleci-cli-to-split-tests/](https://circleci.com/docs/rerun-failed-tests/)https://circleci.com/docs/rerun-failed-tests/) for more details.