updating example to use Swift 5.10 for consistency (#15)

Author: heckj

Package.swift

@@ -1,5 +1,4 @@
-// swift-tools-version:5.5
-// The swift-tools-version declares the minimum version of Swift required to build this package.
+// swift-tools-version:5.10
 
 /*
  This source file is part of the Swift.org open source project
@@ -19,18 +18,18 @@ let package = Package(
         .macOS(.v11)
     ],
     products: [
-        .executable(name: "dealer", targets: ["dealer"]),
+        .executable(name: "dealer",
+                    targets: ["dealer"]),
     ],
     dependencies: [
-        // Dependencies declare other packages that this package depends on.
-        .package(url: "https://github.com/apple/example-package-deckofplayingcards.git",
-                 from: "3.0.0"),
-        .package(url: "https://github.com/apple/swift-argument-parser.git",
-                 from: "0.4.4"),
+        .package(
+            url: "https://github.com/apple/example-package-deckofplayingcards.git",
+            from: "3.0.0"),
+        .package(
+            url: "https://github.com/apple/swift-argument-parser.git",
+            from: "0.4.4"),
     ],
     targets: [
-        // Targets are the basic building blocks of a package. A target can define a module or a test suite.
-        // Targets can depend on other targets in this package, and on products in packages which this package depends on.
         .executableTarget(
             name: "dealer",
             dependencies: [