fix(rpc): rpc client selector

grpc/grpc-go#4717
https://github.com/grpc/grpc-go/releases/tag/v1.42.0
grpc/grpc-go#4817
从 1.42.0 之后，grpc-go 使用 url.Parse 来解析 dial target ，即 "scheme://xxx/xxx" , 之前的 secheme 含有非法字符下划线会导致解析失败。

rpc/client/resolver/resolver.go

@@ -11,7 +11,7 @@ import (
 	"google.golang.org/grpc/resolver"
 )
 
-// "stark_registry:///{service}"
+// "stark-registry:///{service}"
 type builder struct {
 	scheme   string
 	selector *atomic.Value

rpc/client/selector/registry/registry_selector.go

@@ -12,7 +12,7 @@ import (
 	"google.golang.org/grpc/resolver"
 )
 
-const scheme = "stark_registry"
+const scheme = "stark-registry"
 
 var _selector atomic.Value
 

rpc/client/selector/registry/registry_selector_test.go

@@ -1,6 +1,8 @@
 package registry
 
 import (
+	"fmt"
+	"net/url"
 	"testing"
 
 	"github.com/Allenxuxu/stark/rpc/client/selector"
@@ -82,3 +84,11 @@ func TestRegistrySelectorFilter(t *testing.T) {
 	assert.Equal(t, service[0].Name, "foo")
 	assert.Equal(t, service[0].Version, version)
 }
+
+func Test_schema(t *testing.T) {
+	_, err := url.Parse(fmt.Sprintf("%s:///%s", "stark_registry", "test"))
+	assert.Error(t, err)
+
+	_, err = url.Parse(fmt.Sprintf("%s:///%s", "stark-registry", "test"))
+	assert.NoError(t, err)
+}

rpc/client/selector/static/static_selector.go

@@ -11,7 +11,7 @@ import (
 	"google.golang.org/grpc/resolver"
 )
 
-const scheme = "stark_static"
+const scheme = "stark-static"
 
 var _selector atomic.Value