Probe every access review connector on status check

Bad API keys and expired OAuth tokens showed Connected because
probes ran only for OAuth2 and many providers had no ProbeURL.
Add a registry ProbeConnection dispatcher with static, dynamic,
and custom probes so all 41 providers are checked on demand.

Signed-off-by: Bryan Frimin <bryan@probo.com>

pkg/connector/provider/grafana.go

@@ -31,6 +31,7 @@ func grafanaRegistration() *Registration {
 		Provider:       coredata.ConnectorProviderGrafana,
 		DisplayName:    "Grafana",
 		SupportsAPIKey: true,
+		BuildProbeURL:  buildGrafanaProbeURL,
 		ExtraSettings: []ExtraSetting{
 			{Key: "baseUrl", Label: "Base URL", Required: true},
 		},