fix: LoadBalancerUpdateServiceOpts not converted correctly

In the conversion from LoadBalancerUpdateServiceOpts to schema.LoadBalancerActionUpdateServiceRequest, there are conversions from slices to slice pointers. Slice pointers exist in schemas to differentiate between absent and empty.

Goverter converts nil slices to &nil. This leads to the field being marshaled to `null` in JSON (even with the `omitempty` flag) instead of being not present (See hetznercloud/cli#702)

This PR fixes this issue by adding manual conversion methods

hcloud/schema_gen.go

@@ -78,6 +78,8 @@ You can find a documentation of goverter here: https://goverter.jmattheis.de/
 // goverter:extend schemaFromLoadBalancerCreateOptsTargetServer
 // goverter:extend schemaFromLoadBalancerCreateOptsTargetIP
 // goverter:extend stringMapToStringMapPtr
+// goverter:extend int64SlicePtrFromCertificatePtrSlice
+// goverter:extend stringSlicePtrFromStringSlice
 type converter interface {
 
 	// goverter:map Error.Code ErrorCode
@@ -926,3 +928,22 @@ func mapZeroFloat32ToNil(f float32) *float32 {
 func isDeprecationNotNil(d *DeprecationInfo) bool {
 	return d != nil
 }
+
+// this is needed so that a nil slice is mapped to nil instead of &nil
+func int64SlicePtrFromCertificatePtrSlice(s []*Certificate) *[]int64 {
+	if s == nil {
+		return nil
+	}
+	var ids = make([]int64, len(s))
+	for i, cert := range s {
+		ids[i] = cert.ID
+	}
+	return &ids
+}
+
+func stringSlicePtrFromStringSlice(s []string) *[]string {
+	if s == nil {
+		return nil
+	}
+	return &s
+}

hcloud/schema_test.go

@@ -1797,8 +1797,18 @@ func TestLoadBalancerUpdateServiceOptsToSchema(t *testing.T) {
 		Request schema.LoadBalancerActionUpdateServiceRequest
 	}{
 		"empty": {
-			Opts:    LoadBalancerUpdateServiceOpts{},
-			Request: schema.LoadBalancerActionUpdateServiceRequest{},
+			Opts: LoadBalancerUpdateServiceOpts{
+				HTTP: &LoadBalancerUpdateServiceOptsHTTP{},
+				HealthCheck: &LoadBalancerUpdateServiceOptsHealthCheck{
+					HTTP: &LoadBalancerUpdateServiceOptsHealthCheckHTTP{},
+				},
+			},
+			Request: schema.LoadBalancerActionUpdateServiceRequest{
+				HTTP: &schema.LoadBalancerActionUpdateServiceRequestHTTP{},
+				HealthCheck: &schema.LoadBalancerActionUpdateServiceRequestHealthCheck{
+					HTTP: &schema.LoadBalancerActionUpdateServiceRequestHealthCheckHTTP{},
+				},
+			},
 		},
 		"all set": {
 			Opts: LoadBalancerUpdateServiceOpts{