nvim: modules: workspace: Drop key mapping for toggling workspace

Rather than waste a key mapping starting with 'p', we can call this
ourselves when required.

nvim/.config/nvim/lua/modules/workspace.lua

@@ -1,9 +1,5 @@
-local remap = vim.api.nvim_set_keymap
-
 vim.g.workspace_session_directory = vim.fn.expand('~/.vim/session/')
 vim.g.workspace_undodir = vim.fn.expand('~/.vim/undodir')
 vim.g.workspace_autosave = 0
 vim.g.workspace_autosave_ignore = {'gitcommit', 'qf', 'tagbar'}
 vim.g.workspace_session_disable_on_args = 1
-
-remap('n', '<Leader>ps', ':ToggleWorkspace<CR>', { noremap = true })