[Integration] Skip running xcodebuild in the validator

For cross-platform consistency in execution output

lib/cocoapods/validator.rb

@@ -550,7 +550,7 @@ module Pod
     end
 
     def xcodebuild_available?
-      !Executable.which('xcodebuild').nil?
+      !Executable.which('xcodebuild').nil? && ENV['COCOAPODS_VALIDATOR_SKIP_XCODEBUILD'].nil?
     end
 
     FILE_PATTERNS = %i(source_files resources preserve_paths vendored_libraries

spec/integration.rb

@@ -126,11 +126,11 @@ describe_cli 'pod' do
   subject do |s|
     s.executable = "ruby #{ROOT + 'bin/pod'}"
     s.environment_vars = {
-      'CP_REPOS_DIR'             => ROOT + 'spec/fixtures/spec-repos',
-      'COCOAPODS_SKIP_CACHE'     => 'TRUE',
-      'XCODEPROJ_DISABLE_XCPROJ' => 'TRUE',
-      'CLAIDE_DISABLE_AUTO_WRAP' => 'TRUE',
-      'COCOAPODS_DISABLE_STATS'  => 'TRUE',
+      'CLAIDE_DISABLE_AUTO_WRAP'            => 'TRUE',
+      'COCOAPODS_DISABLE_STATS'             => 'TRUE',
+      'COCOAPODS_SKIP_CACHE'                => 'TRUE',
+      'COCOAPODS_VALIDATOR_SKIP_XCODEBUILD' => 'TRUE',
+      'CP_REPOS_DIR'                        => ROOT + 'spec/fixtures/spec-repos',
     }
     s.default_args = [
       '--verbose',