Prevent template files from being committed

Otherwise, it could be interpreted as HTML tags and cause weird rendering.

README.md

@@ -143,7 +143,7 @@ git push origin update_flake_lock_action --force
 ### With a Personal Authentication Token
 
 By providing a Personal Authentication Token, the PR will be submitted in a way that bypasses this limitation (GitHub will essentially think it is the owner of the PAT submitting the PR, and not an Action).
-You can create a token by visiting https://github.com/settings/tokens and select at least the `repo` scope. Then, store this token in your repository secrets (i.e. 'https://github.com/<USER>/<REPO>/settings/secrets/actions') as `GH_TOKEN_FOR_UPDATES` and set up your workflow file like the following:
+You can create a token by visiting https://github.com/settings/tokens and select at least the `repo` scope. Then, store this token in your repository secrets (i.e. `https://github.com/<USER>/<REPO>/settings/secrets/actions`) as `GH_TOKEN_FOR_UPDATES` and set up your workflow file like the following:
 
 ```yaml
 name: update-flake-lock

action.yml

@@ -135,6 +135,12 @@ runs:
       uses: andstor/file-reader-action@v1
       with:
         path: "pr_body.txt"
+    # We need to remove the pr_body files so that the
+    # peter-evans/create-pull-request action does not commit it (the
+    # action commits all new and modified files).
+    - name: Remove PR body template files
+      shell: bash
+      run: rm -f pr_body.txt pr_body.template
     - name: Create PR
       id: create-pr
       uses: peter-evans/create-pull-request@v3