Exclude AggregatedTestResultPublisherTest

jenkinsci/junit-plugin#588 is the issue report
for the JUnit plugin tests that depend on the icon based build status
display.

From jenkinsci/jenkins#8705 the Jenkins core
pull request that switched from using icon based build status to symbol
based build status.  That change also fixes a layout issue in the Safari
web browser.

excludes.txt

@@ -16,3 +16,6 @@ org.jenkinsci.plugins.pipeline.modeldefinition.TriggersTest
 # TODO https://github.com/jenkinsci/pipeline-model-definition-plugin/pull/660
 org.jenkinsci.plugins.pipeline.modeldefinition.endpoints.ErrorsEndpointOpsTest
 org.jenkinsci.plugins.pipeline.modeldefinition.validator.ErrorsJSONParserTest
+
+# TODO https://github.com/jenkinsci/junit-plugin/issues/588
+hudson.tasks.test.AggregatedTestResultPublisherTest