Exclude all refs from spellcheck

For maintenance, it is better not selectively include some files in the spellcheck.

docs/.sphinx/spellingcheck.yaml

@@ -9,13 +9,8 @@ matrix:
     - .custom_wordlist.txt
     output: .sphinx/.wordlist.dic
   sources:
-      # check all files except dconf type in the technical reference
-  - _build/tutorial/**/*.html
-  - _build/explanation/**/*.html
-  - _build/how-to/**/*.html
-  - _build/reference/policies/Computer Policies/Ubuntu/Client management/Computer Scripts/**/*.html|!_build/reference/policies/Computer Policies/Ubuntu/Client management/Power Management/**/*.html
-  - _build/reference/policies/User Policies/Ubuntu/Session management/**/*.html
-  - _build/reference/policies/User Policies/Ubuntu/Peripherals/**/*.html
+      # check all docs except technical reference
+    - _build/**/*.html|!_build/reference/policies/**/*.html
   pipeline:
   - pyspelling.filters.html:
       comments: false