avoid sh word splitting on paths

scripts/source_plugins.sh

@@ -14,14 +14,13 @@ plugin_dir_exists() {
 # No errors if the plugin dir does not exist.
 silently_source_all_tmux_files() {
 	local plugin_path="$1"
-	local plugin_tmux_files="$plugin_path*.tmux"
 	if plugin_dir_exists "$plugin_path"; then
-		for tmux_file in $plugin_tmux_files; do
+		for tmux_file in "$plugin_path"/*.tmux; do
 			# if the glob didn't find any files this will be the
 			# unexpanded glob which obviously doesn't exist
 			[ -f "$tmux_file" ] || continue
 			# runs *.tmux file as an executable
-			$tmux_file >/dev/null 2>&1
+			"$tmux_file" >/dev/null 2>&1
 		done
 	fi
 }