ci: Bump Swatinem/rust-cache to v2.8.1

Author: Techassi

.github/workflows/build.yml

@@ -38,7 +38,7 @@ jobs:
       - uses: dtolnay/rust-toolchain@master
         with:
           toolchain: ${{ env.RUST_TOOLCHAIN_VERSION }}
-      - uses: Swatinem/rust-cache@98c8021b550208e191a6a3145459bfc9fb29c4c0 # v2.8.0
+      - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
         with:
           key: udeps
       - run: cargo install --locked cargo-udeps@0.1.57
@@ -78,7 +78,7 @@ jobs:
         with:
           toolchain: ${{ env.RUST_TOOLCHAIN_VERSION }}
           components: rustfmt
-      - uses: Swatinem/rust-cache@98c8021b550208e191a6a3145459bfc9fb29c4c0 # v2.8.0
+      - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
         with:
           key: doc
       - run: cargo doc --document-private-items
@@ -99,7 +99,7 @@ jobs:
           # for our cases.
           # See: https://github.com/dtolnay/trybuild/issues/236#issuecomment-1620950759
           components: rust-src
-      - uses: Swatinem/rust-cache@98c8021b550208e191a6a3145459bfc9fb29c4c0 # v2.8.0
+      - uses: Swatinem/rust-cache@f13886b937689c021905a6b90929199931d60db1 # v2.8.1
         with:
           key: test
       - run: cargo test --no-default-features --workspace