[Python dist] Add a new job to build arm64 artifacts (grpc#38522)

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Closes grpc#38522

COPYBARA_INTEGRATE_REVIEW=grpc#38522 from XuanWang-Amos:arm64_job 814b718
PiperOrigin-RevId: 718497293

tools/internal_ci/linux/arm64/grpc_distribtests_python_arm64.cfg

@@ -0,0 +1,26 @@
+# Copyright 2025 The gRPC Authors
+#
+# Licensed 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.
+
+# Config file for the internal CI (in protobuf text format)
+
+# Location of the continuous shell script in repository.
+build_file: "grpc/tools/internal_ci/linux/grpc_distribtests_python_arm64.sh"
+timeout_mins: 240
+action {
+  define_artifacts {
+    regex: "**/*sponge_log.*"
+    regex: "github/grpc/reports/**"
+    regex: "github/grpc/artifacts/**"
+  }
+}

tools/internal_ci/linux/grpc_distribtests_python_arm64.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+# Copyright 2025 The gRPC Authors
+#
+# Licensed 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.
+
+set -ex
+
+# change to grpc repo root
+cd $(dirname $0)/../../..
+
+echo "TODO: Building arm64 python artifacts"