preserve stack trace on search history failure

Author: jakelandis

x-pack/qa/smoke-test-watcher-with-security/src/test/java/org/elasticsearch/smoketest/SmokeTestWatcherWithSecurityIT.java

@@ -332,8 +332,8 @@ private ObjectPath getWatchHistoryEntry(String watchId, String state) throws Exc
                 assertThat(watchid, is(watchId));
                 objectPathReference.set(objectPath);
             } catch (ResponseException e) {
-                final String err = "Failed to perform search of watcher history - " + e;
-                logger.info(err);
+                final String err = "Failed to perform search of watcher history";
+                logger.info(err, e);
                 fail(err);
             }
         });

x-pack/qa/smoke-test-watcher/src/test/java/org/elasticsearch/smoketest/SmokeTestWatcherTestSuiteIT.java

@@ -216,8 +216,8 @@ private ObjectPath getWatchHistoryEntry(String watchId) throws Exception {
                 assertThat("watch_id for hit 0 in watcher history", foundWatchId, is(watchId));
                 objectPathReference.set(objectPath);
             } catch (ResponseException e) {
-                final String err = "Failed to perform search of watcher history - " + e;
-                logger.info(err);
+                final String err = "Failed to perform search of watcher history";
+                logger.info(err, e);
                 fail(err);
             }
         });