Support standby replication from GS (GCS) (#1446)

* Add support for manual gs_wal_path in standby
* Remove separate standby version configuration
* Remove setting standby path via cluster/uid/version
Picking up the version doesn't work reliably without making changes to
Spilo. It's clearer to just specify the full S3/GS bucket path.

Co-authored-by: Felix Kunde <felix-kunde@gmx.de>

pkg/apis/acid.zalan.do/v1/crds.go

@@ -649,12 +649,14 @@ var PostgresCRDResourceValidation = apiextv1.CustomResourceValidation{
 						Type: "integer",
 					},
 					"standby": {
-						Type:     "object",
-						Required: []string{"s3_wal_path"},
+						Type: "object",
 						Properties: map[string]apiextv1.JSONSchemaProps{
 							"s3_wal_path": {
 								Type: "string",
 							},
+							"gs_wal_path": {
+								Type: "string",
+							},
 						},
 					},
 					"teamId": {

pkg/apis/acid.zalan.do/v1/postgresql_type.go

@@ -166,6 +166,7 @@ type Patroni struct {
 // StandbyDescription contains s3 wal path
 type StandbyDescription struct {
 	S3WalPath string `json:"s3_wal_path,omitempty"`
+	GSWalPath string `json:"gs_wal_path,omitempty"`
 }
 
 // TLSDescription specs TLS properties