[deps]: Update dtolnay/rust-toolchain digest to 4cda84d (#21948)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/lint.yml

@@ -100,14 +100,14 @@ jobs:
           persist-credentials: false
 
       - name: Install Rust
-        uses: dtolnay/rust-toolchain@4be7066ada62dd38de10e7b70166bc74ed198c30 # stable
+        uses: dtolnay/rust-toolchain@4cda84d5c5c54efe2404f9d843567869ab1699d4 # stable
         with:
           toolchain: 1.96.0
           components: rustfmt, clippy
 
       - name: Install Rust nightly
         id: rust-nightly
-        uses: dtolnay/rust-toolchain@4be7066ada62dd38de10e7b70166bc74ed198c30 # stable
+        uses: dtolnay/rust-toolchain@4cda84d5c5c54efe2404f9d843567869ab1699d4 # stable
         with:
           toolchain: nightly-2026-06-29
           components: rustfmt

.github/workflows/test.yml

@@ -230,7 +230,7 @@ jobs:
           persist-credentials: false
 
       - name: Install rust
-        uses: dtolnay/rust-toolchain@4be7066ada62dd38de10e7b70166bc74ed198c30 # stable
+        uses: dtolnay/rust-toolchain@4cda84d5c5c54efe2404f9d843567869ab1699d4 # stable
         with:
           toolchain: 1.96.0
           components: llvm-tools