On 1.14.x: Merge r1924628, r1934091, r1934092, r1934095, r1934096, r1934116

from trunk:
  GHA: Catch up merge changes for detect-backport-conflicts.yml from trunk.
  Justification:
    Keep GitHub Actions configuration in sync with trunk.
  Votes:
    +1: ivan (only affects GHA)

git-svn-id: https://svn.apache.org/repos/asf/subversion/branches/1.14.x@1935957 13f79535-47bb-0310-9956-ffa450edef68

Author: Ivan Zhakov

.github/workflows/detect-backport-conflicts.yml

@@ -16,16 +16,15 @@
 # specific language governing permissions and limitations
 # under the License.
 #
-# autoconf.yml -- Configuration for autoconf GitHub Action workflow.
+# detect-backport-conflicts.yml -- Configuration for backportbot 
+#   GitHub Action workflow.
 #
 
 name: backportbot
 
 on:
   push:
-    branches: ["1.14.x"]
-  pull_request:
-    branches: ["1.14.x"]
+    branches: ["1.14.x", "1.15.x"]
 
 concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
@@ -42,10 +41,13 @@ jobs:
           sudo apt-get update &&
           sudo apt-get install
           subversion
-          
+
+      - name: Obtain tools/dist
+        run: svn export https://svn.apache.org/repos/asf/subversion/trunk/tools/dist tools-dist
+
       - name: Checkout backport branch
-        run: svn co https://svn.apache.org/repos/asf/subversion/branches/1.14.x
+        run: svn co https://svn.apache.org/repos/asf/subversion/branches/${{ github.ref_name }} branch-wc
 
       - name: Detect conflicting backports
-        run: cd 1.14.x && ./tools/dist/detect-conflicting-backports.py
+        run: cd branch-wc && ../tools-dist/detect-conflicting-backports.py