README.md: Made it explicit that you don't need to use this workflow directly.

Author: CodeGat

README.md

@@ -49,18 +49,10 @@ deploy:
 
 ### `undeploy-*`
 
-For given `spack` environments, we can also remove deployments. For example:
-
-```yml
-remove-prereleases:
-  uses: access-nri/build-cd/.github/workflows/undeploy-2-setup.yml@main
-  with:
-    version-pattern: ${{ inputs.model }}-*
-  secrets: inherit
-```
-
-This will remove every `spack` environment from the deployment target that matches `<model>-*`.
+For given `spack` environments, we can also remove deployments.
 
+> [!NOTE]
+> This workflow is not one that should be used directly. It is used within the automated deployment pipeline to remove prerelease builds of models.
 
 #### Inputs
 
@@ -82,8 +74,6 @@ Using the GitHub Environment, it `ssh`s into the deployment environments `spack`
 
 #### Usage
 
-For given `spack` environments, we can also remove deployments. For example:
-
 ```yml
 remove-prereleases:
   uses: access-nri/build-cd/.github/workflows/undeploy-2-setup.yml@main