Update taiki-e/install-action digest to e8c1cf7 (#298)

Author: nextest-bot

.github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
       - name: Lint (rustfmt)
         run: cargo xfmt --check
       - name: Install cargo readme
-        uses: taiki-e/install-action@bbdef1c33cb8ed1fd122d68d8374ac79998d6960 # v2
+        uses: taiki-e/install-action@e8c1cf74a696e981aec979a6703471e61b400895 # v2
         with:
           tool: cargo-readme
       - name: Run cargo readme