init.lua: removed buildcmd, only needed in keybindings.lua

keybindings.lua: added grep_string to <leader>fs and spell_suggest to
<leader>ss
buildcmd.lua: searches the cwd for a build file and decides which build to use (build.zig, build.bat, build.sh)

init.lua

@@ -1,5 +1,4 @@
 -- Only required if you have packer configured as `opt`
-require('buildcmd')
 require('statusline')
 require('packer_init')
 require('keybindings')