ci: use nightly toolchain for fuzz build

Author: MuNeNiCK

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
         rust: ["1.85.0", stable]
         os: [ubuntu-latest, macos-latest, windows-latest]
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@master
         with:
           toolchain: ${{ matrix.rust }}
@@ -33,7 +33,7 @@ jobs:
   wasm:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
         with:
           targets: wasm32-unknown-unknown
@@ -45,14 +45,16 @@ jobs:
   package:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
       - run: cargo package --workspace --no-verify
 
   fuzz-build:
     runs-on: ubuntu-latest
+    env:
+      RUSTUP_TOOLCHAIN: nightly
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@nightly
       - run: cargo install cargo-fuzz --locked --version 0.13.2
       - run: cargo fuzz build codec
@@ -64,7 +66,7 @@ jobs:
       matrix:
         phoenix: ["~> 1.7.0", "~> 1.8.0"]
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
       - uses: erlef/setup-beam@v1
         with:
@@ -96,7 +98,7 @@ jobs:
           - browser: safari
             os: macos-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
         with:
           targets: wasm32-unknown-unknown