Migration file name date part is generated based on system region settings

[inlineHamed]

When creating new Migration, Migration file name starts with a date part like '20180808120946_MigrationName' .
and this part seems to be used for ordering.
Our problem is if we change our region settings to some calendar other than Georgian (like Persian Calendar) new migration file name are generated based on Persian date that is for example (13970513103708_NewMigrationName) and that breaks the ordering.
In some of my colleagues PCs even after resting the region settings to Georgian new migration names still generates based on Persian Date.

[inlineHamed]

I did a little investigate to find the cause
It seems that this file (https://github.com/aspnet/EntityFrameworkCore/blob/d59be61006d78d507dea07a9779c3c4103821ca3/src/EFCore.Relational/Migrations/Internal/MigrationsIdGenerator.cs)
is responsible for generating migration file names and in this method:

public virtual string GenerateId(string name)
        {
            var now = DateTime.UtcNow;
            var timestamp = new DateTime(now.Year, now.Month, now.Day, now.Hour, now.Minute, now.Second);

            lock (this)
            {
                if (timestamp <= _lastTimestamp)
                {
                    timestamp = _lastTimestamp.AddSeconds(1);
                }

                _lastTimestamp = timestamp;
            }

            return timestamp.ToString(Format) + "_" + name;
}

We see how the time part is generated.
I have created a simple .Net Core Console App to test this function and copy this function into that App and print the result. but even in Systems that we have Persian Migration, this code will print Georgian Date. it's strange ...
so maybe there is a general configuration in the project some where that cause this
hope this help you

[inlineHamed]

@ajcvickers Can you put this into 2.2.0 as it's getting very confusing for us?

[ajcvickers]

@hmdhasani There is potential that when we fix this it could break existing ordering for working applications, so we are planning to do this on the next major version since we try to avoid breaking changes in minor versions.