Update minimum required versions of iOS, tvOS and watchOS to support Swift concurrency

https://www.hackingwithswift.com/quick-start/concurrency/where-is-swift-concurrency-supported

Author: DominikPalo

OAuth2.xcodeproj/project.pbxproj

@@ -953,7 +953,7 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 12.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
 				MACOSX_DEPLOYMENT_TARGET = 10.15;
 				MARKETING_VERSION = 5.3.5;
 				METAL_ENABLE_DEBUG_INFO = YES;
@@ -962,7 +962,7 @@
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
 				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
-				TVOS_DEPLOYMENT_TARGET = 12.0;
+				TVOS_DEPLOYMENT_TARGET = 13.0;
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";
 			};
@@ -1010,14 +1010,14 @@
 				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
 				GCC_WARN_UNUSED_FUNCTION = YES;
 				GCC_WARN_UNUSED_VARIABLE = YES;
-				IPHONEOS_DEPLOYMENT_TARGET = 12.0;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.0;
 				MACOSX_DEPLOYMENT_TARGET = 10.15;
 				MARKETING_VERSION = 5.3.5;
 				METAL_ENABLE_DEBUG_INFO = NO;
 				SDKROOT = iphoneos;
 				SWIFT_VERSION = 5.0;
 				TARGETED_DEVICE_FAMILY = "1,2";
-				TVOS_DEPLOYMENT_TARGET = 12.0;
+				TVOS_DEPLOYMENT_TARGET = 13.0;
 				VALIDATE_PRODUCT = YES;
 				VERSIONING_SYSTEM = "apple-generic";
 				VERSION_INFO_PREFIX = "";

Package.swift

@@ -24,7 +24,7 @@ import PackageDescription
 let package = Package(
 	name: "OAuth2",
 	platforms: [
-		.macOS(.v10_15), .iOS(.v12), .tvOS(.v12), .watchOS(.v5)
+		.macOS(.v10_15), .iOS(.v13), .tvOS(.v13), .watchOS(.v6)
 	],
 	products: [
 		.library(name: "OAuth2", targets: ["OAuth2"]),

README.md

@@ -11,7 +11,7 @@ OAuth2 frameworks for **macOS**, **iOS** and **tvOS** written in Swift 5.
 - [🖥 Sample macOS app][sample] (with data loader examples)
 - [📖 Technical Documentation](https://p2.github.io/OAuth2)
 
-OAuth2 requires Xcode 12.4, the built framework can be used on **OS X 10.15** or **iOS 12** and later.
+OAuth2 requires Xcode 12.4, the built framework can be used on **OS X 10.15**, **iOS 13**, **tvOS** 13, **watchOS 6** and later.
 Happy to accept pull requests, please see [CONTRIBUTING.md](./Docs/CONTRIBUTING.md)
 
 ### Swift Version