* Update silences.md
minor correction in not equals regex
* Update docs/sources/alerting/unified-alerting/silences.md
Co-authored-by: achatterjee-grafana <70489351+achatterjee-grafana@users.noreply.github.com>
(cherry picked from commit e4c80d1269)
Co-authored-by: Andrew Burian <andrew@dapperlabs.com>