proposal: SqlServer connection string detector

[mac2000]

Closes #866

The problem: at moment trufflehog does not see SQL Server connection strings at all 🤷‍♂️

e.g. here is part of Program.cs:

var builder = WebApplication.CreateBuilder(args);

builder.Services
  .AddDbContext<Database>(optionsBuilder => optionsBuilder
    .UseSqlServer("Server=some.domain.com;Initial Catalog=Demo;User ID=sa;Password=PASSWORD_HERE"));

var app = builder.Build();

Proposal: this pull request adds dedicated SQLServer connection string detector to prevent such leaks

How it works

Because connection string itself is a set of case-insensitive key-value pairs delimited by a semicolon with regexp we are looking for something that may be a connection string

To prevent false positives we then try to parse it with msdn.Parse

And if everything fine as a last step we are trying to connect to server with connection string we have found

Also there is an TestSQLServer_pattern with few pattern dedicated tests to see if regexp will match desired strings

[dustin-decker]

Thank you for the contribution!