chore: remove build bot (#5500)

.github/workflows/build_bot.yaml

@@ -1,28 +0,0 @@
-name: Build Bot
-
-on:
-  issue_comment:
-    types: [created]
-
-jobs:
-  dispatch_slash_command:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout source code
-        uses: actions/checkout@v4
-
-      # get build name from pubspec.yaml
-      - name: Get build version
-        working-directory: frontend/appflowy_flutter
-        id: get_build_name
-        run: |
-          echo "fetching version from pubspec.yaml..."
-          echo "build_name=$(grep 'version: ' pubspec.yaml | awk '{print $2}')" >> $GITHUB_OUTPUT
-
-      - uses: peter-evans/slash-command-dispatch@v4
-        with:
-          token: ${{ secrets.PAT }}
-          commands: build
-          static-args: |
-            ref=refs/pull/${{ github.event.issue.number }}/head
-            build_name=${{ steps.get_build_name.outputs.build_name }}