chore(docs): Updated UI Reference (#6221)

Automated changes by [create-pull-request](https://github.com/peter-evans/create-pull-request) GitHub action

Co-authored-by: Oli Juhl <59018053+olivermrbl@users.noreply.github.com>
Co-authored-by: Shahed Nasser <27354907+shahednasser@users.noreply.github.com>

www/apps/ui/src/specs/Button/Button.json

@@ -63,8 +63,12 @@
       "description": "The button's size.",
       "tsType": {
         "name": "union",
-        "raw": "\"base\" \\| \"large\" \\| \"xlarge\"",
+        "raw": "\"small\" \\| \"base\" \\| \"large\" \\| \"xlarge\"",
         "elements": [
+          {
+            "name": "literal",
+            "value": "\"small\""
+          },
           {
             "name": "literal",
             "value": "\"base\""