Update minimum Swift version to 5.10, and add Sendable conformance for effortless Swift 6 usage

Author: kevinrenskers

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:4.2
+// swift-tools-version:5.10
 import PackageDescription
 
 let package = Package(
@@ -11,6 +11,6 @@ let package = Package(
   ],
   targets: [
     .target(name: "PathKit", dependencies: [], path: "Sources"),
-    .testTarget(name: "PathKitTests", dependencies: ["PathKit", "Spectre"], path:"Tests/PathKitTests")
+    .testTarget(name: "PathKitTests", dependencies: ["PathKit", "Spectre"], path:"Tests/PathKitTests", exclude: ["Fixtures"])
   ]
 )

PathKit.podspec

@@ -14,7 +14,7 @@ import Foundation
 
 
 /// Represents a filesystem path.
-public struct Path {
+public struct Path: Sendable {
   /// The character used by the OS to separate two path elements
   public static let separator = "/"
 
@@ -194,7 +194,7 @@ extension Path {
   }
 }
 
-internal protocol FileSystemInfo {
+internal protocol FileSystemInfo: Sendable {
   func isFSCaseSensitiveAt(path: Path) -> Bool
 }