Update taiki-e/install-action digest to d6912b4

Author: renovate[bot]

.github/workflows/rust-coverage.yml

@@ -20,7 +20,7 @@ jobs:
       - name: Install Rust
         run: rustup update stable
       - name: Install cargo-llvm-cov
-        uses: taiki-e/install-action@7a9da991c71dfd905b2ee8252a9ce162f176dc6f
+        uses: taiki-e/install-action@d6912b47771be2c443ec90dbb3d28e023987e782
       - name: Install Clippy
         run: rustup component add clippy
       - name: Install cargo-sonar and run Clippy