config/module: fix regression of ignoring forced type if valid URL

/cc @ceh - Does this break Windows at all? This regressed with your
commit (we didn't have test coverage on it). I added a test now, though.

config/module/detect.go

@@ -41,7 +41,7 @@ func Detect(src string, pwd string) (string, error) {
 	u, err := urlParse(getSrc)
 	if err == nil && u.Scheme != "" {
 		// Valid URL
-		return u.String(), nil
+		return src, nil
 	}
 
 	for _, d := range Detectors {

config/module/detect_test.go

@@ -31,6 +31,12 @@ func TestDetect(t *testing.T) {
 			"git::https://github.com/hashicorp/foo.git//bar",
 			false,
 		},
+		{
+			"git::https://github.com/hashicorp/consul.git",
+			"",
+			"git::https://github.com/hashicorp/consul.git",
+			false,
+		},
 	}
 
 	for i, tc := range cases {