updating swift versions and CI to prep for Swift 6 concurrency

Author: heckj

.github/workflows/build.yml

@@ -10,7 +10,7 @@ jobs:
 
   analyze:
     name: Analyze
-    runs-on: macos-latest
+    runs-on: macos-14
     permissions:
       actions: read
       contents: read
@@ -47,15 +47,12 @@ jobs:
 
   build:
 
-    runs-on: macos-latest
+    runs-on: macos-14
 
     steps:
     - name: Checkout Project
       uses: actions/checkout@v3
 
-    # - name: Switch to Xcode 13.4.1
-    #   run: sudo xcode-select -s /Applications/Xcode_13.4.1.app
-
     - name: Show Build Version
       run: xcodebuild -version
 

.swift-version

@@ -1 +1 @@
-5.5
+5.9

Package.resolved

@@ -1,9 +1,10 @@
-// swift-tools-version:5.5
+// swift-tools-version:5.8
 // The swift-tools-version declares the minimum version of Swift required to build this package.
 
 import Foundation
 import PackageDescription
 
+
 let package = Package(
     name: "SwiftVizScale",
     platforms: [
@@ -30,6 +31,9 @@ let package = Package(
             name: "SwiftVizScale",
             dependencies: [
                 .product(name: "Collections", package: "swift-collections"),
+            ],
+            swiftSettings: [
+                .enableExperimentalFeature("StrictConcurrency")
             ]
         ),
         .target(