feat: enhance Grafana dashboard validation rules

[RottenRat]

Added new grafana-dashboards linters:

• Deprecated Panel Types
• Deprecated Intervals
• Legacy Alert Rules
• Datasource Validation
• Template Variables

Example:

🐒 [grafana (#templates)]
     Message:      Panel 'Incoming Request Duration By Source' uses deprecated type 'graph', consider using
                   'timeseries'
     Module:       istio
     FilePath:     /deckhouse/modules/110-istio/monitoring/grafana-dashboards/istio/service.json

🐒 [grafana (#templates)]
     Message:      Panel 'Incoming Success Rate (non-5xx responses) By Source' uses deprecated type 'graph', consider
                   using 'timeseries'
     Module:       istio
     FilePath:     /deckhouse/modules/110-istio/monitoring/grafana-dashboards/istio/service.json

🐒 [grafana (#templates)]
     Message:      Panel 'Incoming Success Rate (non-5xx responses) By Destination Workload' uses deprecated type
                   'graph', consider using 'timeseries'
     Module:       istio
     FilePath:     /deckhouse/modules/110-istio/monitoring/grafana-dashboards/istio/service.json

🐒 [grafana (#templates)]
     Message:      Panel 'Incoming Request Duration By Service Workload' uses deprecated type 'graph', consider using
                   'timeseries'
     Module:       istio
     FilePath:     /deckhouse/modules/110-istio/monitoring/grafana-dashboards/istio/service.json