protected string MaskPII(string content, MatchEvaluator maskFn) => PIIRegEx.Replace(content, maskFn);
/// <summary>
/// Scrub first part of email
/// </summary>
/// <param name="content"></param>
/// <returns></returns>
public override string Scrub(string content)
=> PIIRegEx.Replace(content, MaskLetters).Replace("@", ".");