Telescope notify – Avoid nil error when nothing is selected

[bjornbm]

Fixes: when no notification selected, either due empty notification history or filter removing all valid selection, a nil error occurred.

E5108: Error executing lua ...r/start/nvim-notify/lua/telescope/_extensions/notify.lua:67: attempt to index local 'selection' (a nil value)
stack traceback:
        ...r/start/nvim-notify/lua/telescope/_extensions/notify.lua:67: in function 'run_replace_or_original'
        ...packer/start/telescope.nvim/lua/telescope/actions/mt.lua:65: in function 'key_func'
        ...k/packer/start/telescope.nvim/lua/telescope/mappings.lua:338: in function 'execute_keymap'
        [string ":lua"]:1: in main chunk
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[rcarriga]

Thanks for the fix!