remove support for versions of Swift <= 5.6

Examples/Simple/Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.5
+// swift-tools-version:5.8
 
 import PackageDescription
 
@@ -13,10 +13,11 @@ let package = Package(
     ],
     dependencies: [
         // this is the dependency on the swift-aws-lambda-runtime library
-        .package(url: "https://github.com/swift-server/swift-aws-lambda-runtime.git", .branch("main")),
+        .package(url: "https://github.com/swift-server/swift-aws-lambda-runtime.git", from: "1.0.0-alpha.2"),
         // this is the dependency on the swift-aws-lambda-events library
         // in real-world projects this would say
         // .package(url: "https://github.com/swift-server/swift-aws-lambda-runtime-events.git", from: "1.0.0")
+        // but here, we're using the local version
         .package(name: "swift-aws-lambda-events", path: "../.."),
     ],
     targets: [

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.7
+// swift-tools-version:5.8
 
 import PackageDescription
 
@@ -12,7 +12,9 @@ let package = Package(
         .package(url: "https://github.com/apple/swift-http-types.git", from: "1.0.0"),
     ],
     targets: [
-        .target(name: "AWSLambdaEvents", dependencies: [.product(name: "HTTPTypes", package: "swift-http-types")]),
-        .testTarget(name: "AWSLambdaEventsTests", dependencies: ["AWSLambdaEvents"]),
+        .target(name: "AWSLambdaEvents",
+                dependencies: [.product(name: "HTTPTypes", package: "swift-http-types")]),
+        .testTarget(name: "AWSLambdaEventsTests",
+                    dependencies: ["AWSLambdaEvents"]),
     ]
 )

docker/Dockerfile

@@ -1,4 +1,4 @@
-ARG swift_version=5.7
+ARG swift_version=5.8
 ARG base_image=swift:$swift_version-amazonlinux2
 FROM $base_image
 # needed to do again after FROM due to docker limitation