fix: <Route> received an unexpected slot "default" (#3115)

* fix: <Route> received an unexpected slot "default"

* Update .changeset/moody-students-report.md

Co-authored-by: Bjorn Lu <[email protected]>

Co-authored-by: Rich Harris <[email protected]>
Co-authored-by: Bjorn Lu <[email protected]>

Author: 3 people

.changeset/moody-students-report.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/kit': patch
+---
+
+fix `<Route> received an unexpected slot "default"` warning

packages/kit/src/core/create_app/index.js

@@ -130,11 +130,13 @@ function generate_app(manifest_data) {
 
 	while (l--) {
 		pyramid = `
-			<svelte:component this={components[${l}]} {...(props_${l} || {})}>
-				{#if components[${l + 1}]}
+			{#if components[${l + 1}]}
+				<svelte:component this={components[${l}]} {...(props_${l} || {})}>				
 					${pyramid.replace(/\n/g, '\n\t\t\t\t\t')}
-				{/if}
-			</svelte:component>
+				</svelte:component>
+			{:else}
+				<svelte:component this={components[${l}]} {...(props_${l} || {})} />
+			{/if}
 		`
 			.replace(/^\t\t\t/gm, '')
 			.trim();