Doc: correct grammar in labels description (#47300)
Doc: correct grammar in labels description (#47300)

Co-authored-by: Adam Gabryś <93ce3bff88d72749d0dcc54b8fa50dc9556f891a@sap.com>
grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana