remove buck2 CI config

.github/workflows/buck2-ci.yml

@@ -1,47 +0,0 @@
-name: CI (Buck2)
-
-on:
-  pull_request:
-  push:
-
-jobs:
-  tests:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v3
-
-      - name: cache buck-out
-        id: buck-out
-        uses: actions/cache@v3
-        with:
-          path: buck-out
-          key: ${{ runner.os }}-buck-out
-
-      - name: buck2 build
-        run: script/buck2 build //... --show-output
-
-      - name: buck2 test
-        run: script/buck2 test //... -- --env PERCY_TOKEN=$PERCY_TOKEN
-        env:
-          PERCY_TOKEN: '${{ secrets.PERCY_TOKEN }}'
-
-      - name: buck2 formatting (with comments)
-        if: github.event.pull_request
-        run: |
-          script/buck2 run //:diff_to_comment -- \
-            --buck2-bin=script/buck2 \
-            --call-fix-command-base="script/buck2 run //:diff_to_comment --" \
-            --review-github-pr \
-            --github-repo=${{ github.repository }} \
-            --github-pr-number=${{ github.event.number }} \
-            $(script/buck2 uquery 'kind("elm_format_diffs|prettier_diffs", //...)')
-        env:
-          GITHUB_TOKEN: '${{ secrets.github_token }}'
-
-      - name: buck2 formatting (without comments)
-        if: "!github.event.pull_request"
-        run: |
-          script/buck2 run //:diff_to_comment -- \
-            --buck2-bin=script/buck2 \
-            --call-fix-command-base="script/buck2 run //:diff_to_comment --" \
-            $(script/buck2 uquery 'kind("elm_format_diffs|prettier_diffs", //...)')