Update workflows to use newer versions of their dependencies

Author: vadage

.github/workflows/build.yml

@@ -14,10 +14,10 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Set up Rust
-        uses: actions-rs/toolchain@v1
+        uses: dtolnay/rust-toolchain@nightly
         with:
           toolchain: nightly
 

.github/workflows/release.yml

@@ -10,10 +10,10 @@ jobs:
 
     steps:
       - name: Checkout code
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
 
       - name: Set up Rust
-        uses: actions-rs/toolchain@v1
+        uses: dtolnay/rust-toolchain@nightly
         with:
           toolchain: nightly