Use Linq query through String instead of ToCharArray when possible

Created by: uwx

Summary

Uses Linq to query the String directly instead of ToCharArray() when not in .NET Standard 1.1, in the DiscordColor constructor.

Details

I noticed you've done the check here but not in the DiscordColor constructor, so I added it.

Changes proposed

• Use Linq query through String instead of ToCharArray when possible

Notes

<3