feat(vpc): parallelize private-network get with errgroup (scaleway#4754)

Author: yfodil

go.mod

@@ -29,6 +29,7 @@ require (
 	github.com/spf13/pflag v1.0.6
 	github.com/stretchr/testify v1.10.0
 	golang.org/x/crypto v0.38.0
+	golang.org/x/sync v0.14.0
 	golang.org/x/term v0.32.0
 	golang.org/x/text v0.25.0
 	gopkg.in/yaml.v3 v3.0.1
@@ -190,7 +191,6 @@ require (
 	go.opentelemetry.io/proto/otlp v1.2.0 // indirect
 	golang.org/x/mod v0.17.0 // indirect
 	golang.org/x/net v0.38.0 // indirect
-	golang.org/x/sync v0.14.0 // indirect
 	golang.org/x/sys v0.33.0 // indirect
 	golang.org/x/time v0.5.0 // indirect
 	google.golang.org/genproto v0.0.0-20240401170217-c3f982113cda // indirect