chore(deps): update dtolnay/rust-toolchain digest to 888c2e1

Author: renovate[bot]

.github/workflows/ci.yml

@@ -30,7 +30,7 @@ jobs:
           submodules: recursive
 
       - name: 🧰 Install MSRV toolchain
-        uses: dtolnay/rust-toolchain@a54c7afa936fefeb4456b2dd8068152669aa8203 # v1
+        uses: dtolnay/rust-toolchain@888c2e1ea69ab0d4330cbf0af1ecc7b68f368cc1 # v1
         with:
           toolchain: ${{ env.MSRV }}