InfluxDB: Fix invalid memory address or nil pointer dereference when schema is missing in URL (#25565)
InfluxDB: Fix invalid memory address or nil pointer dereference when schema is missing in URL (#25565)

Add guard if parsing url fails in influxdb backend data source.

Fixes #25242
grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana,grafana/grafana