Fix bug detecting if go.mod files are nested

go/extractor/cli/go-autobuilder/go-autobuilder.go

@@ -249,8 +249,16 @@ func getDirs(paths []string) []string {
 	return dirs
 }
 
-// Note this has the side effect of sorting `dirs`
-func checkDirsNested(dirs []string) bool {
+func checkDirsNested(inputDirs []string) bool {
+	// replace "." with "" so that we can check if all the paths are nested
+	dirs := make([]string, len(inputDirs))
+	for i, inputDir := range inputDirs {
+		if inputDir == "." {
+			dirs[i] = ""
+		} else {
+			dirs[i] = inputDir
+		}
+	}
 	// the paths were generated by a depth-first search so I think they might
 	// be sorted, but we sort them just in case
 	sort.Strings(dirs)