change from existence to substitution

.vale/fixtures/RedHat/VisualLanguage/testinvalid.adoc

@@ -10,6 +10,5 @@ blue
 purple
 orange
 violet
-next to
 between
 under

.vale/styles/RedHat/VisualLanguage.yml

@@ -1,22 +1,13 @@
 ---
-extends: existence
+extends: substitution
 ignorecase: true
 level: suggestion
 link: https://redhat-documentation.github.io/vale-at-red-hat/docs/main/reference-guide/visuallanguage/
-message: "It is acceptable to use visual styling in documentation, but do not rely solely on visual aspects to convey meaning."
-tokens:
-  - above
-  - below
-  - right
-  - left
-  - top
-  - bottom
-  - green
-  - yellow
-  - blue
-  - purple
-  - orange
-  - violet
-  - next to
-  - between
-  - under
+message: "Do not rely solely on visual language to describe an item."
+action:
+  name: replace
+swap:
+  - above: later|previous|preceding
+  - below: earlier|later|following
+  - top: beginning
+  - bottom: end