feat(gcp): add GCP plugin (#5229)

Add GCP as a supported plugin for dynamic host catalogs

internal/cmd/base/base.go

@@ -38,6 +38,7 @@ const (
 	EnabledPluginAws
 	EnabledPluginHostAzure
 	EnabledPluginMinio
+	EnabledPluginGCP
 )
 
 // MinioEnabled controls if the Minio storage plugin should be initiated or not
@@ -53,6 +54,8 @@ func (e EnabledPlugin) String() string {
 		return "Azure"
 	case EnabledPluginMinio:
 		return "MinIO"
+	case EnabledPluginGCP:
+		return "GCP"
 	default:
 		return ""
 	}