Fish pipe compatibility issues

[miki725]

Current shellpipe="&>" is incompatible with fish which results in error something like:

fish: Expected a command, but instead found a redirection
rg --vimgrep -i foo &> /var/folders/4z/bxmdspnn5qs9x0bbz8w7cbrw0000gn/T/nvimzCL1HW/4

fish is enabled via in ~/.config/nvim/init.vim:

set shell=fish

vim-ripgrep/plugin/vim-ripgrep.vim

Line 89 in ec87af6

let &shellpipe="&>"

[ColinKennedy]

Also noting here that, with a tcsh shell, the default shellpipe is |& tee. Since vim-ripgrep tries to set let &shellpipe="&>", it causes the search to fail. Removing the let &shellpipe="&>" completely worked for me to fix the issue.