refactor: Move MakeUnorderedList into util/string.h to make it reusable

src/util/string.h

@@ -64,6 +64,14 @@ inline std::string Join(const std::vector<std::string>& list, const std::string&
     return Join<std::string>(list, separator);
 }
 
+/**
+ * Create an unordered multi-line list of items.
+ */
+inline std::string MakeUnorderedList(const std::vector<std::string>& items)
+{
+    return Join(items, "\n", [](const std::string& item) { return "- " + item; });
+}
+
 /**
  * Check if a string does not contain any embedded NUL (\0) characters
  */