Update Edit Message to reflect that not every parameter is nullable

[onerandomusername]

These parameters are not all nullable.

[Jiralite]

This is a breaking change, no? What happened?

[vladfrangu]

Is this PR supposed to remove just the nullable callout from the admonition? Because making PATCH not have optional fields is a super breaking change, and I hope that didn't happen

[advaith1]

All patch params are optional and always will be optional.

[onerandomusername]

Apologies, deleted a bit too much. Edited this to be in alignment with what seems to be the actual API behaviour, and with what DV8 committed earlier.

[anthonydiscord]

I was playing around with this and poll, attachments, embeds, and flags can all be null (as long as their is some valid content for the message). Likely some of the others can be as well? Am I missing something or are there any that can't be null? I do think it makes sense to add * for all nullable options even though we call it out above