Fix CI: safe config access in default-hooks, update workflow

default-hooks now uses $env.config? with get -o to avoid
column-not-found errors when running under nu-check without
a config file. Updated setup-nu action to v3.23 and use
working-directory instead of shell:nu cd workaround.

Author: hyiltiz

.github/workflows/test-auto-venv.yml

@@ -16,13 +16,11 @@ jobs:
         steps:
             - uses: actions/checkout@v4
 
-            - uses: hustcer/setup-nu@v3.9
+            - uses: hustcer/setup-nu@v3.23
               with:
                   version: "*"
                   check-latest: true
 
             - name: Run auto-venv tests
-              shell: nu {0}
-              run: |
-                  cd modules/virtual_environments/auto-venv
-                  nu test_auto_venv.nu
+              working-directory: modules/virtual_environments/auto-venv
+              run: nu test_auto_venv.nu

modules/virtual_environments/auto-venv/auto-venv.nu

@@ -19,12 +19,12 @@ export-env {
 
 
 def default-hooks [] {
-    (if ($env.config.hooks.env_change.PWD != null) {
-        $env.config.hooks.env_change.PWD
-    }
-    else {
+    let existing = ($env.config? | default {} | get -o hooks.env_change.PWD)
+    if ($existing != null) {
+        $existing
+    } else {
         []
-    })
+    }
 }
 
 def build-hooks [] {