Update Discord validation

[sadukie]

Need to update the Discord validation:

You no longer need to use the # and 4-digits - per Discord update.

[Micah-Bello]

I'd like to create a PR for this issue

[sadukie]

@ardalis Heads up on this one.

@Micah-Bello We don't want just the validation to be removed. What should happen is:

• Discord username should be optional. (unless this is required for devBetter)
• Validation still needs to be in place to check that it meets the guidelines. The validation needs updated to meet the latest in naming guidelines from Discord.

Tagging in @ShadyNagy since he helped us address this in another one of our codebases.

[ardalis]

We still need this - just ran into it again today.

[ardalis]

@canro91 can you take this one?

[canro91]

@ardalis Sure, I'm taking it.