Update actions/checkout action to v2 (#277)

Co-authored-by: Renovate Bot <bot@renovateapp.com>

.github/workflows/rust.yml

@@ -13,7 +13,7 @@ jobs:
     - uses: hecrj/setup-rust-action@v1
       with:
         rust-version: stable
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - name: cargo fmt
       run: cargo fmt -- --check
 
@@ -26,7 +26,7 @@ jobs:
     - uses: hecrj/setup-rust-action@v1
       with:
         rust-version: stable
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - name: Run tests
       run: cargo test -- --skip=feature_tests
 
@@ -45,7 +45,7 @@ jobs:
     - uses: hecrj/setup-rust-action@v1
       with:
         rust-version: stable
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - name: Run tests
       run: cargo test -- feature_tests
 
@@ -56,7 +56,7 @@ jobs:
     - uses: hecrj/setup-rust-action@v1
       with:
         rust-version: stable
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - name: Build release binary
       run: cargo build --release
       env:
@@ -77,7 +77,7 @@ jobs:
     - uses: hecrj/setup-rust-action@v1
       with:
         rust-version: stable
-    - uses: actions/checkout@v1
+    - uses: actions/checkout@v2
     - name: Build release binary
       run: cargo build --release
       env: