Add error and expected errors in rally_benchmark_malformed_template t…

…est package

test/packages/false_positives/rally_benchmark_malformed_template.expected_errors

@@ -0,0 +1 @@
+<error>failed to initialize backfill generator for scenario &#34;logs-benchmark&#34;: template: generator:12: unexpected &#34;}&#34; in operand</error>

test/packages/false_positives/rally_benchmark_malformed_template/_dev/benchmark/rally/logs-benchmark/template.ndjson

@@ -1,7 +1,7 @@
 {{- $timestamp := generate "timestamp" -}}
 {
 "@timestamp": "{{ $timestamp.Format "2006-01-02T15:04:05.999999Z07:00" }}",
-"data_stream.type": "logs",
+data_stream.type": "logs",
 "data_stream.dataset": "rally_benchmarks.testds",
 "data_stream.namespace": "ep",
 "container.id": "{{ generate "container.id" }}",
@@ -11,4 +11,4 @@
 "log.offset": {{ generate "log.offset" }},
 "tags": ["rally_benchmark.testds", "forwarded", "{{ generate "tags" }" ],
 "message": "{{ generate "IP" }} - - [{{ $timestamp.Format "02/Jan/2006:15:04:05.999999 -0700" }}] \"GET /favicon.ico HTTP/1.1\" {{ generate "StatusCode" }} {{ generate "Size" }} \"http://{{ generate "Hostname" }}:{{ generate "Port" }}/\" \"skip-this-one/5.0 (Macintosh; Intel Mac OS X 10_12_0) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.59 Safari/537.36\""
-}
+}