fix(metrics): add injection type to operator

The operator was not announcing the TYPE_INSTANCE_SIDECAR_INJECTION
capability so the CNPG operator was not considering the plugin enabled.
However, this bug was masked if you had set `isWALArchiver` to `true`
in your config, the backward compatibility code was marking the plugin
as enabled as a side-effect.

Signed-off-by: Kenny Root <kenny@the-b.org>

internal/cnpgi/operator/identity.go

@@ -62,6 +62,13 @@ func (i IdentityImplementation) GetPluginCapabilities(
 					},
 				},
 			},
+			{
+				Type: &identity.PluginCapability_Service_{
+					Service: &identity.PluginCapability_Service{
+						Type: identity.PluginCapability_Service_TYPE_INSTANCE_SIDECAR_INJECTION,
+					},
+				},
+			},
 		},
 	}, nil
 }