[New Data Source]: openobserve

### Background Regarding plugins for openobserver with grafana and prometheus agent with grafana. ### Use case i need to show the metrics and logs from the OpenObserve dashboard. Also, i want to configure prometheus agent with grafana not from prometheus server. ### Contribution - [ ] Are you looking to create the plugin? - [ ] Are you affiliated with the project/product the data source integrates with? - [ ] Does the plugin integrate with a commercial product?