ci: pin Rust toolchain to 1.84.0 (tested version)

Author: eprifti

.github/workflows/rust.yml

@@ -17,6 +17,7 @@ jobs:
       - uses: actions/checkout@v5
       - uses: actions-rust-lang/setup-rust-toolchain@v1
         with:
+          toolchain: 1.84.0
           rustflags: ""
           components: clippy,rustfmt
       - name: Format check
@@ -40,6 +41,8 @@ jobs:
             target/
           key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
       - uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          toolchain: 1.84.0
       - name: Build
         run: cargo build --locked --workspace --all-features --verbose
       - name: Unit and lib tests
@@ -62,5 +65,7 @@ jobs:
             target/
           key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
       - uses: actions-rust-lang/setup-rust-toolchain@v1
+        with:
+          toolchain: 1.84.0
       - name: Full test suite (lib + integration e2e)
         run: cargo test --locked --workspace --all-features --verbose -- --test-threads=2