cl-button Font-Size is unset

[DougAnderson444]

Hey there,

I've been experimenting with your library, it's really great.

I have noticed that the button sizes are not set in the library css, causing sometimes the buttons in inherit a (much larger) font size of parent.

https://github.com/nenadpnc/cl-editor/blob/bdb90d267dee0aeeee35e5be68f7273c33c2aea5/src/Editor.svelte#L186

I think is a css font-size: .4em; is added here, this should help fix the button size when embedded in other apps.