Add Swift 5.9 manifest

Package.swift

@@ -45,7 +45,6 @@ let package = Package(
 )
 
 var swiftSettings: [SwiftSetting] { [
-    .enableUpcomingFeature("ExistentialAny"),
     .enableUpcomingFeature("ConciseMagicFile"),
     .enableUpcomingFeature("ForwardTrailingClosures"),
     .enableUpcomingFeature("ImportObjcForwardDeclarations"),

Package@swift-5.9.swift

@@ -0,0 +1,57 @@
+// swift-tools-version:5.9
+import PackageDescription
+
+let package = Package(
+    name: "mysql-kit",
+    platforms: [
+        .macOS(.v10_15),
+        .iOS(.v13),
+        .watchOS(.v6),
+        .tvOS(.v13),
+    ],
+    products: [
+        .library(name: "MySQLKit", targets: ["MySQLKit"]),
+    ],
+    dependencies: [
+        .package(url: "https://github.com/vapor/mysql-nio.git", from: "1.7.1"),
+        .package(url: "https://github.com/vapor/sql-kit.git", from: "3.29.2"),
+        .package(url: "https://github.com/vapor/async-kit.git", from: "1.19.0"),
+        .package(url: "https://github.com/apple/swift-crypto.git", "2.0.0" ..< "4.0.0"),
+        .package(url: "https://github.com/apple/swift-nio.git", from: "2.64.0"),
+        .package(url: "https://github.com/apple/swift-nio-ssl.git", from: "2.26.0"),
+    ],
+    targets: [
+        .target(
+            name: "MySQLKit",
+            dependencies: [
+                .product(name: "AsyncKit", package: "async-kit"),
+                .product(name: "MySQLNIO", package: "mysql-nio"),
+                .product(name: "SQLKit", package: "sql-kit"),
+                .product(name: "Crypto", package: "swift-crypto"),
+                .product(name: "NIOFoundationCompat", package: "swift-nio"),
+                .product(name: "NIOSSL", package: "swift-nio-ssl"),
+            ],
+            swiftSettings: swiftSettings
+        ),
+        .testTarget(
+            name: "MySQLKitTests",
+            dependencies: [
+                .product(name: "SQLKitBenchmark", package: "sql-kit"),
+                .target(name: "MySQLKit"),
+            ],
+            swiftSettings: swiftSettings
+        ),
+    ]
+)
+
+var swiftSettings: [SwiftSetting] { [
+    .enableUpcomingFeature("ExistentialAny"),
+    .enableUpcomingFeature("ConciseMagicFile"),
+    .enableUpcomingFeature("ForwardTrailingClosures"),
+    .enableUpcomingFeature("ImportObjcForwardDeclarations"),
+    .enableUpcomingFeature("DisableOutwardActorInference"),
+    .enableUpcomingFeature("IsolatedDefaultValues"),
+    .enableUpcomingFeature("GlobalConcurrency"),
+    .enableUpcomingFeature("StrictConcurrency"),
+    .enableExperimentalFeature("StrictConcurrency=complete"),
+] }