chore: use capo cluster agent for API requests

At the moment, we do not modify the user agent for all API requests
we make which make it hard to identify if certain requests were
done by CAPO or not.

This change prepends the CAPO version to the Gophercloud user
agent which will give plenty of benefits.

pkg/scope/provider.go

@@ -37,6 +37,7 @@ import (
 
 	infrav1 "sigs.k8s.io/cluster-api-provider-openstack/api/v1alpha7"
 	"sigs.k8s.io/cluster-api-provider-openstack/pkg/clients"
+	"sigs.k8s.io/cluster-api-provider-openstack/version"
 )
 
 const (
@@ -152,6 +153,10 @@ func NewProviderClient(cloud clientconfig.Cloud, caCert []byte, logger logr.Logg
 		return nil, nil, "", fmt.Errorf("create providerClient err: %v", err)
 	}
 
+	ua := gophercloud.UserAgent{}
+	ua.Prepend(fmt.Sprintf("cluster-api-provider-openstack/%s", version.Get().String()))
+	provider.UserAgent = ua
+
 	config := &tls.Config{
 		MinVersion: tls.VersionTLS12,
 	}