Fix workflows wrt linkcheck addition

Author: willcrichton

.github/workflows/beta.yml

@@ -25,5 +25,5 @@ jobs:
         uses: peaceiris/actions-gh-pages@v3
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
-          publish_dir: ./book
+          publish_dir: ./book/html
           destination_dir: beta

.github/workflows/main.yml

@@ -25,4 +25,4 @@ jobs:
         uses: peaceiris/actions-gh-pages@v3
         with:
           github_token: ${{ secrets.GITHUB_TOKEN }}
-          publish_dir: ./book
+          publish_dir: ./book/html

.github/workflows/release.yml

@@ -22,10 +22,10 @@ jobs:
 
       - name: Compress book
         run: zip -r -9 crp.zip *
-        working-directory: book
+        working-directory: book/html
 
       - name: Release book
         uses: softprops/action-gh-release@v2
         with:
           files: |
-            book/crp.zip
+            book/html/crp.zip