Enable vale for prose linting (#3)

* Enable vale in CI

* Add vale config

* Tweak vale

* Update config

* Update .gitignore

* Switch back

* Rename CI

* Add badges

* Tidy up CI

* Change image

* Configure vale

* Delint

* Update README

.github/styles/RedHat/UserReplacedValues.yml

@@ -0,0 +1,16 @@
+---
+extends: existence
+level: suggestion
+message: "Separate words by underscores in user-replaced values."
+link: https://redhat-documentation.github.io/vale-at-red-hat/docs/main/reference-guide/userreplacedvalues/
+scope: raw
+nonword: true
+action:
+  name: edit
+  params:
+    - regex
+    - "(-)" # pattern
+    - "_" # replace
+tokens:
+  - '__<[a-z_\x60]+-[\x60a-z_-]+>__'
+  - '<[a-z_]+-[a-z_-]+>'