fix: include undefined in types for getEntry with content layer (#12601)

Author: ascorbic

.changeset/fuzzy-bats-try.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Includes "undefined" in types for getEntry

packages/astro/templates/content/types.d.ts

@@ -92,7 +92,9 @@ declare module 'astro:content' {
 		collection: C,
 		id: E,
 	): E extends keyof DataEntryMap[C]
-		? Promise<DataEntryMap[C][E]>
+		? string extends keyof DataEntryMap[C]
+			? Promise<DataEntryMap[C][E]> | undefined
+			: Promise<DataEntryMap[C][E]>
 		: Promise<CollectionEntry<C> | undefined>;
 
 	/** Resolve an array of entry references from the same collection */