Update README

Author: sarahchen6

README.md

@@ -34,7 +34,7 @@ Images are built per PR for ease in testing. These test images are prefixed with
 To test these images in `dd-trace-java` CI:
 
 1. Open a PR in [DataDog/dd-trace-java-docker-build](https://github.com/DataDog/dd-trace-java-docker-build) with the changes you want to test. Let's say these changes are made in PR #N.
-2. After the PR images are built in the [GitHub Container Registry](https://github.com/DataDog/dd-trace-java-docker-build/pkgs/container/dd-trace-java-docker-build), run the [Create test image mirror PR](https://github.com/DataDog/dd-trace-java-docker-build/actions/workflows/create-test-mirror-pr.yml) workflow with the corresponding PR number: `N`. This automatically opens a PR in [DataDog/images](https://github.com/DataDog/images) that adds mirror entries for the `N_merge-*` test images. Merge the PR that should be automatically approved by the `dd-prapprover` bot.
+2. After the PR images are built in the [GitHub Container Registry](https://github.com/DataDog/dd-trace-java-docker-build/pkgs/container/dd-trace-java-docker-build), run the [Create test image mirror PR](https://github.com/DataDog/dd-trace-java-docker-build/actions/workflows/create-test-mirror-pr.yml) workflow with the corresponding PR number: `N`. This automatically opens a PR in [DataDog/images](https://github.com/DataDog/images) that adds mirror entries for the `N_merge-*` test images. Merge the PR that should be automatically approved by the `dd-prapprover` bot. After merging, the images may take 30 min or more to update.
 3. Open a PR in [DataDog/dd-trace-java](https://github.com/DataDog/dd-trace-java) that sets `BUILDER_IMAGE_VERSION_PREFIX: "N_merge-"` in `.gitlab-ci.yml`. Here, you can check your test images with `DataDog/dd-trace-java` CI.
 4. Every time you want to test changes made in PR #N, ensure the test image SHAs in `DataDog/images` are updated by running the [Create test image mirror PR](https://github.com/DataDog/dd-trace-java-docker-build/actions/workflows/create-test-mirror-pr.yml) workflow with `N`. Confirm that these PRs are approved and merged by the `dd-prapprover` bot.
 5. When the test images look good and `DataDog/dd-trace-java` CI is green, merge your `DataDog/dd-trace-java-docker-build` PR #N.