add the guide to update aqua-checksums.json via autofix.ci

docs/guides/checksum.md

@@ -199,3 +199,46 @@ Then `test` job would fail because the checksum is unmatched.
 ```
 time="2023-03-12T06:36:05Z" level=fatal msg="aqua failed" actual_checksum=A8E55BEA1A5F94F9515FD9C5C3296D1874461BA1DBD158B3FC0ED6A0DB3B7D91 aqua_version=2.28.0 env=linux/amd64 error="checksum is invalid" exe_name=tfcmt expected_checksum=A8E55BEA1A5F94F9515FD9C5C3296D1874461BA1DBD158B3FC0ED6A0DB3B7D92 package=suzuki-shunsuke/tfcmt package_version=v4.1.0 program=aqua
 ```
+
+## :bulb: Update aqua-checksums.json using autofix.ci
+
+Instead of [update-checksum-action](https://github.com/aquaproj/update-checksum-action) and [update-checksum-workflow](https://github.com/aquaproj/update-checksum-workflow), you can use `aqua upc` command and [autofix.ci](https://autofix.ci/).
+
+About autofix.ci, please see the website. https://autofix.ci/
+autofix.ci is free for OSS.
+autofix.ci has various benefits:
+
+- You can fix pull requests from fork securely
+- Easy to use. You don't need to take care of how to create and push commits
+- Commits are verified
+- You no longer need to branch processing based on whether the pull request is from a fork or not
+
+We're using autofix.ci in various places.
+
+e.g. https://github.com/aquaproj/aqua-renovate-config/blob/main/.github/workflows/autofix.yaml
+
+This is an example workflow:
+
+```yaml
+name: autofix.ci
+on: pull_request
+permissions: {}
+jobs:
+  autofix:
+    runs-on: ubuntu-24.04
+    permissions: {}
+    timeout-minutes: 15
+    steps:
+      - name: Checkout the repository
+        uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
+        with:
+          persist-credentials: false
+      - name: Install aqua
+        uses: aquaproj/aqua-installer@e2d0136abcf70b7a2f6f505720640750557c4b33 # v3.1.1
+        with:
+          aqua_version: v2.43.0
+      - name: Fix aqua-checksums.json
+        run: aqua upc -prune
+      - name: Run autofix.ci
+        uses: autofix-ci/action@2891949f3779a1cafafae1523058501de3d4e944 # v1.3.1
+```