Update for Neovim 0.7.0

[alexghergh]

Following the release of Neovim 0.7.0, the keymap Lua API is improved. The code should change to reflect that.

[Diablo-D3]

local tmux = require('nvim-tmux-navigation')

tmux.setup {
    disable_when_zoomed = true
}

vim.keymap.set('n', "<C-h>", tmux.NvimTmuxNavigateLeft)
vim.keymap.set('n', "<C-j>", tmux.NvimTmuxNavigateRight)
vim.keymap.set('n', "<C-k>", tmux.NvimTmuxNavigateUp)
vim.keymap.set('n', "<C-l>", tmux.NvimTmuxNavigateDown)
vim.keymap.set('n', "<C-\\>", tmux.NvimTmuxNavigateLastActive)
vim.keymap.set('n', "<C-Space>", tmux.NvimTmuxNavigateNext)

[alexghergh]

Pushed a commit to reflect the changes. Thank you for the example code!

Closing the issue.