perf(tree): reduce allocations in findCaseInsensitivePath

Author: arturmelanchyk

tree.go

@@ -671,12 +671,7 @@ walk: // Outer loop for walking the tree
 func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) ([]byte, bool) {
 	const stackBufSize = 128
 
-	// Use a static sized buffer on the stack in the common case.
-	// If the path is too long, allocate a buffer on the heap instead.
-	buf := make([]byte, 0, stackBufSize)
-	if length := len(path) + 1; length > stackBufSize {
-		buf = make([]byte, 0, length)
-	}
+	buf := make([]byte, 0, max(stackBufSize, len(path)+1))
 
 	ciPath := n.findCaseInsensitivePathRec(
 		path,