Update taiki-e/install-action digest to 2b51c05 (#192)

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@6da51af62171044932d435033daa70a0eb3383ba # v2
+        uses: taiki-e/install-action@2b51c05cf7315a16dcec651726da87c70e45b990 # v2
         with:
           tool: cargo-readme
       - name: Run cargo readme