ci(deps): update dtolnay/rust-toolchain digest to 439cf60 (#396)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| dtolnay/rust-toolchain | action | digest | `1482605` -> `439cf60` |

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.github/workflows/build.yml

@@ -54,7 +54,7 @@ jobs:
         run: |
           sudo apt-get install -y musl-tools --no-install-recommends
       - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4.0.0
-      - uses: dtolnay/rust-toolchain@1482605bfc5719782e1267fd0c0cc350fe7646b8 # master
+      - uses: dtolnay/rust-toolchain@439cf607258077187679211f12aa6f19af4a0af7 # master
         with:
           toolchain: stable
           target: ${{ matrix.target }}