Updating AudioKit dependency to be based on version number instead of branch

Author: aure

Package.resolved

@@ -7,7 +7,7 @@ let package = Package(
     name: "STKAudioKit",
     platforms: [.macOS(.v10_14), .iOS(.v13), .tvOS(.v13)],
     products: [.library(name: "STKAudioKit", targets: ["STKAudioKit"])],
-    dependencies: [.package(url: "https://github.com/AudioKit/AudioKit", .branch("develop"))],
+    dependencies: [.package(url: "https://github.com/AudioKit/AudioKit", from: "5.2.0")],
     targets: [
         .target(name: "Stk", exclude: ["LICENSE"], resources: [.copy("rawwaves")]),
         .target(name: "STKAudioKit", dependencies: ["AudioKit", "CSTKAudioKit", "Stk"]),