Use yaml vs yml ext.

Author: slominskir

.github/workflows/gh-pages-publish.yml renamed to .github/workflows/gh-pages-publish.yaml

@@ -1,12 +1,12 @@
 # python-workflows
 GitHub Action Python workflows
 
-| Name                 | Description                      |
-|----------------------|----------------------------------|
-| [gh-pages-publish.yml](https://github.com/JeffersonLab/python-workflows/blob/main/.github/workflows/gh-pages-publish.yml) | Publish API docs to GitHub Pages |
-| [gh-release.yml](https://github.com/JeffersonLab/python-workflows/blob/main/.github/workflows/gh-release.yml) | Create a GitHub Release |
-| [pypi-publish.yml](https://github.com/JeffersonLab/python-workflows/blob/main/.github/workflows/pypi-publish.yml) | Publish an artifact on PyPi |
-| [unit-ci.yml](https://github.com/JeffersonLab/python-workflows/blob/main/.github/workflows/unit-ci.yml) | Build and run Unit tests |
+| Name                                                                                                                        | Description                      |
+|-----------------------------------------------------------------------------------------------------------------------------|----------------------------------|
+| [gh-pages-publish.yaml](https://github.com/JeffersonLab/python-workflows/blob/main/.github/workflows/gh-pages-publish.yaml) | Publish API docs to GitHub Pages |
+| [gh-release.yaml](https://github.com/JeffersonLab/python-workflows/blob/main/.github/workflows/gh-release.yaml)             | Create a GitHub Release          |
+| [pypi-publish.yaml](https://github.com/JeffersonLab/python-workflows/blob/main/.github/workflows/pypi-publish.yaml)         | Publish an artifact on PyPi      |
+| [unit-ci.yaml](https://github.com/JeffersonLab/python-workflows/blob/main/.github/workflows/unit-ci.yaml)                   | Build and run Unit tests         |
 
 ## Workflow Updates
 Workflows are versioned in semver just as with regular software, however, the GitHub Action workflows convention is to reference a major version number such that backwards compatible minor and patch updates are received automatically.  This means a separate major tag such as `v1` must be moved after each release.  To move a major tag after a release execute (`v1` shown):