Implemented the Outdated subcommand (#6)

This PR contains the work done to implement the `Outdated` subcommand that check for outdated package dependencies in a *Hummingbird* project.

Reviewed-on: #6
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

Library/Sources/Internal/Extensions/URL+Extensions.swift

@@ -16,7 +16,7 @@ extension URL {
     
     var pathString: String {
         if #available(macOS 13.0, *) {
-            path(percentEncoded: true)
+            path(percentEncoded: false)
         } else {
             path
         }

Library/Sources/Public/Tasks/OutdatedDependenciesTask.swift

@@ -0,0 +1,31 @@
+import Foundation
+
+public struct OutdatedDependenciesTask {
+
+    // MARK: Properties
+    
+    private let terminalService: TerminalServicing
+    
+    // MARK: Initialisers
+    
+    public init(terminalService: TerminalServicing) {
+        self.terminalService = terminalService
+    }
+    
+    // MARK: Functions
+    
+    public func callAsFunction(at location: URL? = nil) async throws (TerminalServiceError) {
+        let executableURL = URL(at: "/usr/bin/swift")
+        
+        var arguments: [String] = ["package", "update"]
+        
+        if let location {
+            arguments.append(contentsOf: ["--package-path", location.pathString])
+        }
+        
+        arguments.append("--dry-run")
+        
+        try await terminalService.run(executableURL, arguments: arguments)
+    }
+    
+}