bg_h0 too blue for gruvbox

[D0J0P]

Most of the dark backgrounds for gruvbox dark mode are neutral(#282828) with many warm background and foreground colors. bg_h0, which is #1d2021, has an rgb profile of 29, 32, 33, which differs from the gruvbox theme of having warm or neutral colors for backgrounds. Something like #1d1d1d would at least make it completely neutral.