[SWIFT] Add Antlr4Dynamic product

Signed-off-by: Grzegorz Spryszyński <[email protected]>

Author: GrzegorzSpryszynski-TomTom

Package.swift

@@ -12,6 +12,10 @@ let package = Package(
             name: "Antlr4Static",
             type: .static,
             targets: ["Antlr4"]),
+        .library(
+            name: "Antlr4Dynamic",
+            type: .dynamic,
+            targets: ["Antlr4"]),
     ],
     targets: [
         .target(