fix(ios-template): added workaround for Cocoapods bug in XC15 (#6847)

ios-template/App/Podfile

@@ -1,5 +1,18 @@
 require_relative '../../node_modules/@capacitor/ios/scripts/pods_helpers'
 
+# workaround for Xcode 15 and Cocoapods 1.21.1
+# Should not be needed after Cocoapods 1.13.0
+def fixToolChainDirectory(installer)
+  installer.pods_project.targets.each do |target|
+    target.build_configurations.each do |config|
+      xcconfig_path = config.base_configuration_reference.real_path
+      xcconfig = File.read(xcconfig_path)
+      xcconfig_mod = xcconfig.gsub(/DT_TOOLCHAIN_DIR/, "TOOLCHAIN_DIR")
+      File.open(xcconfig_path, "w") { |file| file << xcconfig_mod }
+    end
+  end
+end
+
 platform :ios, '13.0'
 use_frameworks!
 
@@ -20,4 +33,5 @@ end
 
 post_install do |installer|
   assertDeploymentTarget(installer)
+  fixToolChainDirectory(installer)
 end