chore: corrects dateFNS keys, stricter types

test/buildConfigWithDefaults.ts

@@ -27,6 +27,7 @@ import {
 } from '@payloadcms/richtext-lexical'
 import { de } from '@payloadcms/translations/languages/de'
 import { en } from '@payloadcms/translations/languages/en'
+import { es } from '@payloadcms/translations/languages/es'
 // import { slateEditor } from '@payloadcms/richtext-slate'
 import { type Config, buildConfig } from 'payload/config'
 import sharp from 'sharp'
@@ -173,16 +174,18 @@ export async function buildConfigWithDefaults(
     }),
     sharp,
     telemetry: false,
-    i18n: {
-      supportedLanguages: {
-        en,
-        de,
-      },
-    },
     typescript: {
       declare: false,
     },
     ...testConfig,
+    i18n: {
+      supportedLanguages: {
+        en,
+        es,
+        de,
+      },
+      ...(testConfig?.i18n || {}),
+    },
   }
 
   config.admin = {