Bump dtolnay/rust-toolchain

Bumps [dtolnay/rust-toolchain](https://github.com/dtolnay/rust-toolchain) from 56f84321dbccf38fb67ce29ab63e4754056677e0 to f7ccc83f9ed1e5b9c81d8a67d7ad1a747e22a561.
- [Release notes](https://github.com/dtolnay/rust-toolchain/releases)
- [Commits](dtolnay/rust-toolchain@56f8432...f7ccc83)

---
updated-dependencies:
- dependency-name: dtolnay/rust-toolchain
  dependency-version: f7ccc83f9ed1e5b9c81d8a67d7ad1a747e22a561
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/mirror.yml

@@ -127,7 +127,7 @@ jobs:
           fetch-depth: 0
 
       - name: Setup Rust
-        uses: dtolnay/rust-toolchain@56f84321dbccf38fb67ce29ab63e4754056677e0 # stable
+        uses: dtolnay/rust-toolchain@f7ccc83f9ed1e5b9c81d8a67d7ad1a747e22a561 # stable
         with:
           toolchain: stable