codeium does not fallback to existing tab mapping to coc-vim

[Hritik14]

I've the following tab mapping to coc

inoremap <expr> <Tab> 
      \ coc#pum#visible() ? coc#pum#confirm() : 
      \ coc#expandableOrJumpable() ? "\<C-r>=coc#rpc#request('doKeymap', ['snippets-expand-jump',''])\<CR>" :
      \ CheckBackspace() ? "\<Tab>" : 
      \ coc#refresh()

let g:coc_snippet_next = '<tab>'
let g:coc_snippet_prev = '<s-tab>'

Now, whenever no codeium suggestion is available, it should ideally fall back to the above mapping but it inserts a literal tab instead.