Use Xcode14 (#533)

Author: nzagorchev

.travis.yml

@@ -4,11 +4,11 @@ if: |
   ((commit_message != 'update spm') AND (sender != env(GITHUB_NAME)))
 
 language: objective-c
-osx_image: xcode13.4
+osx_image: xcode14
 
 xcode_workspace: Leanplum.xcworkspace
 xcode_scheme: LeanplumSDKApp
-xcode_destination: platform=iOS Simulator,OS=15.0,name=iPhone 12
+xcode_destination: platform=iOS Simulator,OS=16.0,name=iPhone 14
 
 cache: cocoapods
 podfile: Podfile