Update Markdown.md

Author: Ryu0118

Sources/Markdown/Markdown.docc/Markdown.md

@@ -6,7 +6,7 @@ Swift `Markdown` is a Swift package for parsing, building, editing, and analyzin
 
 The parser is powered by GitHub-flavored Markdown's [cmark-gfm](https://github.com/github/cmark-gfm) implementation, so it follows the spec closely. As the needs of the community change, the effective dialect implemented by this library may change.
 
-The markup tree provided by this package is comprised of immutable/persistent, thread-safe, copy-on-write value types that only copy substructure that has changed. Other examples of the main strategy behind this library can be seen in Swift's [lib/Syntax](https://github.com/apple/swift/tree/master/lib/Syntax) and its Swift bindings, [SwiftSyntax](https://github.com/apple/swift-syntax).
+The markup tree provided by this package is comprised of immutable/persistent, thread-safe, copy-on-write value types that only copy substructure that has changed. Other examples of the main strategy behind this library can be seen in [SwiftSyntax](https://github.com/apple/swift-syntax).
 
 ## Topics