Correct title casing inconsistencies (#1033)

Author: amirhhashemi

src/routes/solid-router/concepts/alternative-routers.mdx

@@ -1,5 +1,5 @@
 ---
-title: Alternative Routers
+title: Alternative routers
 ---
 
 While the default router uses the browser's `location.pathname` to determine the current route, you can use alternative routers to change this behavior.

src/routes/solid-router/concepts/nesting.mdx

@@ -1,5 +1,5 @@
 ---
-title: Nesting Routes
+title: Nesting routes
 ---
 
 Nested routes are a way to create a hierarchy of routes in your application.

src/routes/solid-start/advanced/websocket.mdx

@@ -1,5 +1,5 @@
 ---
-title: WebSocket Endpoint
+title: WebSocket endpoint
 ---
 
 WebSocket endpoint may be included by passing the ws handler file you specify in your start config.