Pattern not matched issue

Hello,

I have an issue where some containerd logs are failing to be matched. Example error message from fluentd:

Error from calicos log
```
2022-05-16 05:09:38.523746465 +0000 fluent.warn: {"message":"[fluentd-containers.log] pattern not matched: \"2022-05-16T05:09:38.482863939Z stdout F 2022-05-16 05:09:38.482 [INFO][63] felix/summary.go 100: Summarising 10 dataplane reconciliation loops over 1m2.9s: avg=22ms longest=195ms ()\""}
```

Error from calico-accountant log
```
2022-05-16 05:09:44.515427977 +0000 fluent.warn: {"message":"[fluentd-containers.log] pattern not matched: \"2022-05-16T05:09:43.751745039Z stderr F W0516 05:09:43.751605 1 collector.go:73] Dropping scrape; all 0 counters are below minimum count of 0\""}
```

Im using v0.1.1 and fluent-plugin-concat v2.5.0.