Give another example for multiline. (#3138)
Give another example for multiline. (#3138)

* Give another example for multiline.

Summary:
This is a new example I've tested. It uses the zero-width space
character `U+200B` to identify the first line of a multline block.

* Update docs/sources/clients/promtail/stages/multiline.md

Co-authored-by: Cyril Tovena <1f3b43b4f8eb8a957255fd6382cb431f49248e69@gmail.com>

* Apply suggestions from code review

Co-authored-by: Cyril Tovena <1f3b43b4f8eb8a957255fd6382cb431f49248e69@gmail.com>
grafana/loki,grafana/loki,grafana/loki,grafana/loki,grafana/loki,grafana/loki