bump cspell-action to v6.9.0 (#8368)

Author: Nightblade

.github/workflows/spellcheck.yml

@@ -33,7 +33,7 @@ jobs:
             ${{ env.CONFIG_URL }}/contribs-dict.txt
 
       - name: Run cspell
-        uses: streetsidesoftware/cspell-action@v5
+        uses: streetsidesoftware/cspell-action@v6.9.0
         with:
           files: '**' # needed as workaround for non-incremental runs (overrides in config still work ok)
           config: "cspell.json"