Add Concurrent Multi-Session IME test apk

This test apk will host the concurrent multi-session IME tests.
For now, it will be enabled for Android Auto only.

Bug: 304358981
Test: atest ConcurrentMultiSessionImeTest
Change-Id: I437acbd1ce72868292add242fc38aeff9a548add
diff --git a/tests/inputmethod/ConcurrentMultiSessionImeTest/AndroidManifest.xml b/tests/inputmethod/ConcurrentMultiSessionImeTest/AndroidManifest.xml
new file mode 100644
index 0000000..0defe5b
--- /dev/null
+++ b/tests/inputmethod/ConcurrentMultiSessionImeTest/AndroidManifest.xml
@@ -0,0 +1,23 @@
+<?xml version="1.0" encoding="utf-8"?><!--
+  Copyright (C) 2023 The Android Open Source Project
+
+  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.
+-->
+
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.android.server.inputmethod.multisessiontest">
+
+    <instrumentation
+        android:name="androidx.test.runner.AndroidJUnitRunner"
+        android:targetPackage="com.android.server.inputmethod.multisessiontest"></instrumentation>
+</manifest>