Upgrade peaceiris/actions-mdbook GitHub Action from 1 to 2 version (#…

…328)

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/ci.yml

@@ -161,7 +161,7 @@ jobs:
       - uses: dtolnay/rust-toolchain@v1
         with:
           toolchain: stable
-      - uses: peaceiris/actions-mdbook@v1
+      - uses: peaceiris/actions-mdbook@v2
 
       - run: make test.book
 
@@ -275,7 +275,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: peaceiris/actions-mdbook@v1
+      - uses: peaceiris/actions-mdbook@v2
 
       - run: make book.build
                   out=gh-pages/${{ (github.ref == 'refs/heads/main'