Add supported platforms

Package.resolved

@@ -1,14 +1,16 @@
 {
-  "pins" : [
-    {
-      "identity" : "swift-docc-plugin",
-      "kind" : "remoteSourceControl",
-      "location" : "https://github.com/apple/swift-docc-plugin",
-      "state" : {
-        "revision" : "3303b164430d9a7055ba484c8ead67a52f7b74f6",
-        "version" : "1.0.0"
+  "object": {
+    "pins": [
+      {
+        "package": "SwiftDocCPlugin",
+        "repositoryURL": "https://github.com/apple/swift-docc-plugin",
+        "state": {
+          "branch": null,
+          "revision": "3303b164430d9a7055ba484c8ead67a52f7b74f6",
+          "version": "1.0.0"
+        }
       }
-    }
-  ],
-  "version" : 2
+    ]
+  },
+  "version": 1
 }

Package.swift

@@ -1,4 +1,4 @@
-// swift-tools-version:5.6
+// swift-tools-version:5.5
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import PackageDescription
@@ -7,7 +7,10 @@ let package = Package(
     name: "AsyncHTTP",
     platforms: [
         .iOS(.v15),
-        .macOS(.v12)
+        .macOS(.v12),
+        .macCatalyst(.v15),
+        .tvOS(.v15),
+        .watchOS(.v8)
     ],
     products: [
         .library(name: "AsyncHTTP", targets: ["AsyncHTTP"]),