use -writeable-system not -system-writable

Author: dellis1972

build-tools/automation/yaml-templates/run-systemapp-tests.yaml

@@ -26,7 +26,7 @@ jobs:
         solution: tests/Mono.Android-Tests/Mono.Android-Tests.csproj
         configuration: $(XA.Build.Configuration)
         msbuildArguments: >-
-          /t:AcquireAndroidTarget /p:TestEmulatorArguments=-system-writeable /bl:$(System.DefaultWorkingDirectory)/bin/Test$(XA.Build.Configuration)/start-emulator.binlog
+          /t:AcquireAndroidTarget /p:TestEmulatorArguments=-writable-system /bl:$(System.DefaultWorkingDirectory)/bin/Test$(XA.Build.Configuration)/start-emulator.binlog
 
     - template: run-nunit-tests.yaml
       parameters: