Adapt to Account being an AutoValue

Change-Id: I16cdac3d89f1a89102876f96b3eec1c34f4f52fc
diff --git a/src/main/java/com/googlesource/gerrit/plugins/uploadvalidator/ValidatorConfig.java b/src/main/java/com/googlesource/gerrit/plugins/uploadvalidator/ValidatorConfig.java
index 5630b48..f9f30c0 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/uploadvalidator/ValidatorConfig.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/uploadvalidator/ValidatorConfig.java
@@ -86,7 +86,7 @@
     return conf != null
         && isValidConfig(conf, projectName)
         && (activeForRef(conf, refName))
-        && (activeForEmail(conf, user.getAccount().getPreferredEmail()))
+        && (activeForEmail(conf, user.getAccount().preferredEmail()))
         && (activeForProject(conf, projectName.get()))
         && (!hasCriteria(conf, "skipGroup")
             || !canSkipValidation(conf, validatorOp)