warning sumneko_lua is deprecated at nvim startup

[Woynert]

sumneko_lua is deprecated, use lua_ls instead. See :h deprecated
This function will be removed in lspconfig version 0.2.0
stack traceback:
        .../site/pack/packer/start/nvim-lspconfig/lua/lspconfig.lua:41: in function '__index'
        .../pack/packer/start/lsp-zero.nvim/lua/lsp-zero/server.lua:19: in function 'configure'
        ...im/site/pack/packer/start/lsp-zero.nvim/lua/lsp-zero.lua:86: in function 'setup_server'
        ...ck/packer/start/lsp-zero.nvim/lua/lsp-zero/installer.lua:138: in function 'use'
        ...im/site/pack/packer/start/lsp-zero.nvim/lua/lsp-zero.lua:89: in function 'setup'

nvim-lspconfig PR sumneko_lua -> lua_ls