feat: Remove tpm as submodule and automate installation of tpm from tmux.conf

.gitmodules

@@ -1,3 +0,0 @@
-[submodule "plugins/tpm"]
-	path = plugins/tpm
-	url = https://github.com/tmux-plugins/tpm

tmux.conf

@@ -64,5 +64,8 @@ set -g @plugin "nordtheme/tmux"
 # set -g @plugin 'git@github.com:user/plugin'
 # set -g @plugin 'git@bitbucket.com:user/plugin'
 
+# Automatically install tpm
+if "test ! -d ~/.tmux/plugins/tpm" "run 'git clone https://github.com/tmux-plugins/tpm ~/.tmux/plugins/tpm && ~/.tmux/plugins/tpm/bin/install_plugins'"
+
 # Initialize TMUX plugin manager (keep this line at the very bottom of tmux.conf)
 run  "${HOME}/.config/tmux/plugins/tpm/tpm"