docs: api v1.42: add missing "force" query arg on plugin disable

This option was added in 8cb2229cd18c53bdbf36301f26db565a50027d6a for
API version 1.28, but forgot to update the documentation and version
history.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

docs/api/v1.42.yaml

@@ -10345,6 +10345,12 @@ paths:
             default if omitted.
           required: true
           type: "string"
+        - name: "force"
+          in: "query"
+          description: |
+            Force disable a plugin even if still in use.
+          required: false
+          type: "boolean"
       tags: ["Plugin"]
   /plugins/{name}/upgrade:
     post: