Use apache/arrow main

Author: kou

.github/workflows/rc.yml

@@ -309,13 +309,19 @@ jobs:
         shell: bash
         run: |
           tar -xf apache-arrow-java-*.tar.gz --strip-components=1
-      - name: Download the latest Apache Arrow C++
-        if: github.event_name != 'schedule'
-        shell: bash
-        run: |
-          ci/scripts/download_cpp.sh
+      # We always use the main branch for apache/arrow for now.
+      # Because we want to use
+      # https://github.com/apache/arrow/pull/47749 in
+      # apache/arrow-java. We can revert this workaround once Apache
+      # Arrow 22.0.0 that includes the change released.
+      #
+      # - name: Download the latest Apache Arrow C++
+      #   if: github.event_name != 'schedule'
+      #   shell: bash
+      #   run: |
+      #     ci/scripts/download_cpp.sh
       - name: Checkout Apache Arrow C++
-        if: github.event_name == 'schedule'
+        # if: github.event_name == 'schedule'
         uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
         with:
           repository: apache/arrow