formatted conda completion and used helper function

completion/available/conda.completion.bash

@@ -1,4 +1,11 @@
-#!/usr/bin/env bash
-which register-python-argcomplete > /dev/null \
-  && eval "$(register-python-argcomplete conda)" \
-  || echo "Please install argcomplete to use conda completion"
+# shellcheck shell=bash
+cite "about-completion"
+about-completion "conda completion"
+
+if _command_exists conda; then
+	if _command_exists register-python-argcomplete; then
+		eval "$(register-python-argcomplete conda)"
+	else
+		_log_warning "Argcomplete not found. Please run 'conda install argcomplete'"
+	fi
+fi