Update Swatinem/rust-cache action to v2.8.1

Author: oxide-renovate[bot]

.github/workflows/ci.yml

@@ -20,7 +20,7 @@ jobs:
       - uses: dtolnay/rust-toolchain@stable
         with:
           components: rustfmt, clippy
-      - uses: Swatinem/rust-cache@98c8021b550208e191a6a3145459bfc9fb29c4c0 # v2.8.0
+      - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
         with:
           key: partition-${{ matrix.partition }}
       - name: Install just, cargo-hack, and cargo-sync-rdme
@@ -60,7 +60,7 @@ jobs:
       - uses: dtolnay/rust-toolchain@master
         with:
           toolchain: ${{ matrix.rust-version }}
-      - uses: Swatinem/rust-cache@98c8021b550208e191a6a3145459bfc9fb29c4c0 # v2.8.0
+      - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
         with:
           key: partition-${{ matrix.partition }}
       - uses: taiki-e/install-action@cargo-hack
@@ -89,7 +89,7 @@ jobs:
       - uses: dtolnay/rust-toolchain@master
         with:
           toolchain: ${{ matrix.rust-version }}
-      - uses: Swatinem/rust-cache@98c8021b550208e191a6a3145459bfc9fb29c4c0 # v2.8.0
+      - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
       - uses: taiki-e/install-action@cross
       - name: Check
         run: cross check --target thumbv7em-none-eabi --no-default-features -p iddqd
@@ -105,7 +105,7 @@ jobs:
         with:
           toolchain: nightly
           components: miri
-      - uses: Swatinem/rust-cache@98c8021b550208e191a6a3145459bfc9fb29c4c0 # v2.8.0
+      - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
       - uses: taiki-e/install-action@cargo-hack
       - uses: taiki-e/install-action@nextest
       # Run tests for all crates containing unsafe code. Currently, that's just