ci: fix docs step

Author: levinzonr

.github/workflows/docs.yml

@@ -19,7 +19,7 @@ jobs:
           python-version: 3.x
       - run: echo "cache_id=$(date --utc '+%V')" >> $GITHUB_ENV
       - run: |
-          ./gradle dokkaHtmlMultiModule
+          ./gradlew dokkaHtmlMultiModule
           mv build/dokka/htmlMultiModule docs/api
       - uses: actions/cache@v4
         with: