Update taiki-e/install-action digest to 7ea888a (#212)

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@ae97ff9daf1cd2e216671a047d80ff48461e30bb # v2
+        uses: taiki-e/install-action@7ea888af71a31437ad4e71c62d021b3bb2728ea9 # v2
         with:
           tool: cargo-readme
       - name: Run cargo readme