Fix flogger compile time errors

Change-Id: Idb1909e1e4314bc86ed328bbfc5151b7292f12f0
diff --git a/src/main/java/com/googlesource/gerrit/plugins/its/base/validation/ItsValidateComment.java b/src/main/java/com/googlesource/gerrit/plugins/its/base/validation/ItsValidateComment.java
index 074b882..f4c7ce0 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/its/base/validation/ItsValidateComment.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/its/base/validation/ItsValidateComment.java
@@ -79,7 +79,7 @@
                   "Failed to check whether or not issue "
                       + issueId
                       + " exists, due to connectivity issue. Commit will be accepted.";
-              logger.atWarning().withCause(e).log(synopsis);
+              logger.atWarning().withCause(e).log("%s", synopsis);
               details = e.toString();
               existenceCheckResult = ItsExistenceCheckResult.CONNECTIVITY_FAILURE;
               ret.add(commitValidationFailure(synopsis, details, existenceCheckResult));