home: direnv: lib: fix shellcheck directive

I like it better with a space in it.

modules/home/direnv/lib/android.sh

@@ -1,4 +1,4 @@
-#shellcheck shell=bash
+# shellcheck shell=bash
 
 # shellcheck disable=2155
 use_android() {

modules/home/direnv/lib/nix.sh

@@ -1,4 +1,4 @@
-#shellcheck shell=bash
+# shellcheck shell=bash
 
 use_pkgs() {
     if ! has nix; then

modules/home/direnv/lib/postgres.sh

@@ -1,4 +1,4 @@
-#shellcheck shell=bash
+# shellcheck shell=bash
 
 layout_postgres() {
     if ! has postgres || ! has initdb; then

modules/home/direnv/lib/python.sh

@@ -1,4 +1,4 @@
-#shellcheck shell=bash
+# shellcheck shell=bash
 
 layout_poetry() {
     if ! has poetry; then