Add missing parameters to Embed

[davidhozic]

Summary

Related PR: #1996

The Embed is missing some parameters.

What is the feature request for?

The core library

The Problem

Currently the Embed object doesn't accept all the parameters at start and instead set's some of them through functions:

• Embed.set_footer,
• Embed.set_image and
• Embed.set_thumbnail

which requires extra work to define it and is a bit unpractical.

Additionaly, for some reason, discord.types.embed.Embed defines these parameters in the annotations which makes it seem like they were planned, but never realized.

The Ideal Solution

I propose to allow definition of these parameters at Embed definition.

The Current Solution

No response

Additional Context

No response