Fix release-branch Jenkins builds (#14121)

* bring back Jenkins makefile and requirements.txt

* Try using CHANGE_ID to identify pull requests everywhere.

* Remove slashes from dockerfile tag

Authored-by: David Riazati <driazati@users.noreply.github.com>

Author: areusch

ci/jenkins/Makefile

@@ -0,0 +1,27 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+_venv: requirements.txt
+	rm -rf _venv
+	python3 -mvenv _venv
+	_venv/bin/pip3 install -r requirements.txt
+
+all: _venv
+	_venv/bin/python3 generate.py
+
+.PHONY: all venv
+.DEFAULT_GOAL=all