chore: bump gitlab-ai-provider to 5.3.1 for GPT-5.4 model support (#18849)

Author: vglafirov

bun.lock

@@ -121,7 +121,7 @@
     "drizzle-orm": "catalog:",
     "effect": "catalog:",
     "fuzzysort": "3.1.0",
-    "gitlab-ai-provider": "5.2.2",
+    "gitlab-ai-provider": "5.3.1",
     "glob": "13.0.5",
     "google-auth-library": "10.5.0",
     "gray-matter": "4.0.3",