ci: upgrade CI hosts to Xcode 15.1

https://developer.apple.com/documentation/xcode-release-notes/xcode-15-release-notes
https://developer.apple.com/documentation/xcode-release-notes/xcode-15_0_1-release-notes
https://developer.apple.com/documentation/xcode-release-notes/xcode-15_1-release-notes

Signed-off-by: Jakub Sokołowski <jakub@status.im>

ci/Jenkinsfile.ios

@@ -5,7 +5,7 @@ library 'status-jenkins-lib@v1.8.4'
 def isPRBuild = utils.isPRBuild()
 
 pipeline {
-  agent { label 'macos && arm64 && nix-2.14 && xcode-14.3' }
+  agent { label 'macos && arm64 && nix-2.14 && xcode-15.1' }
 
   parameters {
     string(

nix/overlay.nix

@@ -69,7 +69,7 @@ in {
   yarn = super.yarn.override { nodejs = super.nodejs-18_x; };
   openjdk = super.openjdk11_headless;
   xcodeWrapper = super.xcodeenv.composeXcodeWrapper {
-    version = "14.0";
+    version = "15.0";
     allowHigher = true;
   };
   go = super.go_1_19;

nix/status-go/mobile/default.nix

@@ -19,7 +19,7 @@
 
   ios = {targets ? [ "ios/arm64" "iossimulator/amd64"]}: callPackage ./build.nix {
     platform = "ios";
-    platformVersion = "8.0";
+    platformVersion = "11.0";
     outputFileName = "Statusgo.xcframework";
     inherit meta source goBuildLdFlags targets;
   };