update mod list tags tests

Signed-off-by: Tihomir Jovicic <tihomir.jovicic.develop@gmail.com>

cmd/dagger/cmd/mod/file.go

@@ -66,6 +66,10 @@ func read(f io.Reader) (*file, error) {
 		return nil, err
 	}
 
+	if len(lines) == 0 {
+		return nil, fmt.Errorf("mod file is empty")
+	}
+
 	var module string
 	if split := strings.Split(lines[0], " "); len(split) > 1 {
 		module = strings.Trim(split[1], "\"")

cmd/dagger/cmd/mod/repo_test.go

@@ -66,7 +66,7 @@ func TestListTags(t *testing.T) {
 
 	r, err := clone(&require{
 		prefix:  "https://",
-		repo:    "github.com/cuelang/cue",
+		repo:    "github.com/tjovicic/gcpcloudrun-cue",
 		path:    "",
 		version: "",
 	}, tmpDir)