DateTimeOffset should preserve offset

[JProgrammer]

Currently the DateTimeOffset extension method has the unexpected behavior of changing the offset to match that of the current system timezone and does not just set the time as suggested by the name.

This change copies the offset to the new DateTimeOffset

[JonathanMagnan]

Hello @JProgrammer ,

Thank you for your pull request,

We will review it

Best Regards,

Jonathan

---

Performance Libraries
context.BulkInsert(list, options => options.BatchSize = 1000);
Entity Framework Extensions • Entity Framework Classic • Bulk Operations • Dapper Plus

Runtime Evaluation
Eval.Execute("x + y", new {x = 1, y = 2}); // return 3
C# Eval Function • SQL Eval Function