update bitflags to v2

.github/workflows/ci.yml

@@ -45,7 +45,7 @@ jobs:
         if: matrix.target.os == 'windows-latest'
         run: echo 'OPENSSL_DIR=C:\Program Files\OpenSSL-Win64' | Out-File -FilePath $env:GITHUB_ENV -Append
 
-      - name: Install ${{ matrix.version }}
+      - name: Install Rust (${{ matrix.version }})
         uses: actions-rust-lang/setup-rust-toolchain@v1
         with:
           toolchain: ${{ matrix.version }}

.github/workflows/upload-doc.yml

@@ -3,6 +3,13 @@ name: Upload documentation
 on:
   push: { branches: [master] }
 
+permissions:
+  contents: write
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   build:
     permissions: