GHA: Bump Xcode versions

12.x not available anymore.

.github/workflows/swift.yml

@@ -13,33 +13,20 @@ jobs:
       - name: Select latest available Xcode
         uses: maxim-lobanov/[email protected]
         with:
-          xcode-version: 12.4
+          xcode-version: 14.2
       - name: Checkout Repository
         uses: actions/checkout@v2
       - name: Build Swift Debug Package
         run: swift build -c debug
       - name: Build Swift Release Package
         run: swift build -c release
   iOS:
-    runs-on: macos-latest
-    steps:
-      - name: Select latest available Xcode
-        uses: maxim-lobanov/[email protected]
-        with:
-          xcode-version: 12.4
-      - name: Checkout Repository
-        uses: actions/checkout@v2
-      - name: Prerequisites
-        run: gem install xcpretty
-      - name: Build
-        run: set -o pipefail; xcodebuild -scheme UXKit-UIKit build | xcpretty --color
-  iOS15:
-    runs-on: macos-latest
+    runs-on: macos-13
     steps:
       - name: Select latest available Xcode
         uses: maxim-lobanov/[email protected]
         with:
-          xcode-version: 13.2
+          xcode-version: '15.0.0'
       - name: Checkout Repository
         uses: actions/checkout@v2
       - name: Prerequisites
@@ -64,12 +51,12 @@ jobs:
       - name: Build
         run: set -o pipefail; xcodebuild -scheme UXKit -destination "platform=iOS Simulator,OS=15.2,name=iPhone 13 Pro" build | xcpretty --color
   NeXTstep:
-    runs-on: macos-latest
+    runs-on: macos-13
     steps:
       - name: Select latest available Xcode
         uses: maxim-lobanov/[email protected]
         with:
-          xcode-version: 12.4
+          xcode-version: '15.0.0'
       - name: Checkout Repository
         uses: actions/checkout@v2
       - name: Prerequisites