Add test filtering, iterations, and custom result path

[naftaly]

This PR adds test control and result management features to the xcodebuild action:

• Test iterations: Run each test multiple times to identify flaky tests via test-iterations input
• Test filtering: Selectively run or skip specific tests using only-testing and skip testing inputs (multiline format: TestTarget/TestClass/testMethod)
• Custom result path: Specify a custom path for the .xcresult bundle with result bundle-path input