fix(data collections): normalize file paths for DataEntry.id (#8144)

* normalize file paths for DataEntry.id

* add changeset

Author: lilnasy

.changeset/twenty-mirrors-remember.md

@@ -0,0 +1,5 @@
+---
+'astro': patch
+---
+
+Fixed an issue where data entries' id included backslashes instead of forward slashes on Windows.

packages/astro/src/content/utils.ts

@@ -209,7 +209,7 @@ export function getDataEntryId({
 	collection,
 }: Pick<ContentPaths, 'contentDir'> & { entry: URL; collection: string }): string {
 	const relativePath = getRelativeEntryPath(entry, collection, contentDir);
-	const withoutFileExt = relativePath.replace(new RegExp(path.extname(relativePath) + '$'), '');
+	const withoutFileExt = normalizePath(relativePath).replace(new RegExp(path.extname(relativePath) + '$'), '');
 
 	return withoutFileExt;
 }