Add NetworkSecurityUnitTests to tethering-mainline-presubmit

Test with connectivity/tethering module only, to catch integration issues with older versions of other modules.

Only the unit test are added to the test_mapping for now. The CTS tests are not compatible with older dessert releases.

The min_sdk_version in the test build target should help preventing the
regressions from b/398885474.

Bug: 397130276
Test: on go/abtd
Change-Id: I215758a34901ff048a8279b4a417ef9f4797db0f

networksecurity/TEST_MAPPING

@@ -1,4 +1,9 @@
 {
+  "tethering-mainline-presubmit": [
+    {
+      "name": "NetworkSecurityUnitTests"
+    }
+  ],
   "presubmit": [
     {
       "name": "CtsNetSecConfigCertificateTransparencyTestCases"

networksecurity/tests/unit/Android.bp

@@ -41,4 +41,5 @@ android_test {
     ],
 
     sdk_version: "test_current",
+    min_sdk_version: "VanillaIceCream",
 }

networksecurity/tests/unit/AndroidTest.xml

@@ -17,6 +17,12 @@
 <configuration description="Runs NetworkSecurity Mainline unit Tests.">
     <option name="test-tag" value="NetworkSecurityUnitTests" />
 
+    <!--
+        Only run tests if the device under test is SDK version 35 (Android 15) or above.
+    -->
+    <object type="module_controller"
+            class="com.android.tradefed.testtype.suite.module.Sdk35ModuleController" />
+
     <target_preparer class="com.android.tradefed.targetprep.suite.SuiteApkInstaller">
         <option name="test-file-name" value="NetworkSecurityUnitTests.apk" />
     </target_preparer>