fix: 🐛 treat isActive to case-insensitive

✅ Closes: #3656

Author: Kyle-Ye

src/util/route.js

@@ -118,8 +118,8 @@ function isObjectEqual (a = {}, b = {}): boolean {
 
 export function isIncludedRoute (current: Route, target: Route): boolean {
   return (
-    current.path.replace(trailingSlashRE, '/').indexOf(
-      target.path.replace(trailingSlashRE, '/')
+    current.path.replace(trailingSlashRE, '/').toLowerCase().indexOf(
+      target.path.replace(trailingSlashRE, '/').toLowerCase()
     ) === 0 &&
     (!target.hash || current.hash === target.hash) &&
     queryIncludes(current.query, target.query)