Remove unused braces from html! macro

[ranile]

Description

Remove unused braces from the macro's generated code.

Fixes #2157

Checklist

• I have run cargo make pr-flow
• I have reviewed my own code
• I have added tests

[Madoshakalaka]

removing the braces causes the #[allow(clippy::unit_arg)] to be applied to an expression, which is an unstable feature.
I think the change is not trivial and I have worked out a different version. Will submit a PR in a moment!

[ranile]

removing the braces causes the #[allow(clippy::unit_arg)] to be applied to an expression, which is an unstable feature. I think the change is not trivial and I have worked out a different version. Will submit a PR in a moment!

Ah, I see. I'll fix it in this PR.

[ranile]

Nevermind, my fix didn't work. @Madoshakalaka if you wanna try, go ahead.