fix: #126 support for descendant API

[saikrishna321]

This pull request updates the dependency installation process across CI/CD workflows, adds support for new Flutter locator strategies, and updates related test cases. The most important changes are grouped below.

Dependency Management Improvements:

• Replaces npm ci and npm install with npm install --no-package-lock in CI/CD scripts (.circleci/config.yml, .github/workflows/main.yml, .github/workflows/test.yml) to avoid creating or using a package-lock.json file during automated installs. [1] [2] [3] [4] [5]
• Updates wdio-android-ci and wdio-ios-ci scripts in package.json to use npm install --no-package-lock for subproject dependency installation.
• Bumps the wdio-flutter-by-service dependency version from ^1.0.11 to ^1.2.0 in package.json, ensuring compatibility with new locator strategies.

Flutter Locator Strategy Enhancements:

• Adds support for -flutter descendant and -flutter ancestor locator strategies in the AppiumFlutterDriver's supported locator list (src/driver.ts).
• Updates the findElOrEls command to parse the selector as JSON when using -flutter descendant or -flutter ancestor, enabling complex selector objects.

Test Improvements:

• Replaces the "Nested Scroll Test" with a new "Descendant Test" in test/specs/test.e2e.js to validate the new descendant locator strategy.

[sudharsan-selvaraj]

LGTM🤟🏻