Revert "[tests] try to use jdk 11 for device tests (dotnet#6033)"

This reverts commit d14f4a2.

Author: jonathanpeppers

build-tools/automation/azure-pipelines.yaml

@@ -1033,7 +1033,7 @@ stages:
     parameters:
       job_name: mac_msbuilddevice_tests
       job_suffix: Legacy
-      jdkTestFolder: $(XA.Jdk11.Folder)
+      jdkTestFolder: $(XA.Jdk8.Folder)
 
   # Check - "Xamarin.Android (MSBuild Emulator Tests macOS - One .NET)"
   - template: yaml-templates/run-msbuild-device-tests.yaml