[feature request] Option to set absolute height and width in g:fzf_layout

[noib3]

• I have fzf 0.22.0 or above
• I have read through https://github.com/junegunn/fzf.vim/blob/master/README.md
• I have read through https://github.com/junegunn/fzf/blob/master/README-VIM.md
• I have read through the manual page of fzf (man fzf)
• I have searched through the existing issues

Right now I have in my init.vim something like

let g:fzf_layout = { 'window': { 'width': 1, 'height': 0.3 } }

which sets the width of the popup terminal to 100% of the available space, and its height to 30%.

It'd be nice to be able to set absolute values for height and width, for example I'm fine with having 'width': 1, but I'd like to set 'height' to a fixed value of 10 lines, regardless of the available space. Can this be implemented?