Docs validation function - Add meaningful errors

[subkanthi]

The following function just prints right/left error which is not very meaningful and very difficult to troubleshoot.

def check_doc_files(yaml_files: Dict[str, Dict]):
    print("Checking doc files")
    current_doc_urls = []
    current_logo_urls = []
    for provider in yaml_files.values():
        if 'integrations' in provider:
            current_doc_urls.extend(
                guide
                for guides in provider['integrations']
                if 'how-to-guide' in guides
                for guide in guides['how-to-guide']
            )
            current_logo_urls.extend(
                integration['logo'] for integration in provider['integrations'] if 'logo' in integration
            )
        if 'transfers' in provider:
            current_doc_urls.extend(
                op['how-to-guide'] for op in provider['transfers'] if 'how-to-guide' in op
            )
    expected_doc_urls = {
        "/docs/" + os.path.relpath(f, start=DOCS_DIR)
        for f in glob(f"{DOCS_DIR}/apache-airflow-providers-*/operators/**/*.rst", recursive=True)
        if not f.endswith("/index.rst") and '/_partials' not in f
    }
    expected_doc_urls |= {
        "/docs/" + os.path.relpath(f, start=DOCS_DIR)
        for f in glob(f"{DOCS_DIR}/apache-airflow-providers-*/operators.rst", recursive=True)
    }
    expected_logo_urls = {
        "/" + os.path.relpath(f, start=DOCS_DIR)
        for f in glob(f"{DOCS_DIR}/integration-logos/**/*", recursive=True)
        if os.path.isfile(f)
    }
    try:
        assert_sets_equal(set(expected_doc_urls), set(current_doc_urls))
        assert_sets_equal(set(expected_logo_urls), set(current_logo_urls))
    except AssertionError as ex:
        print(ex)
        sys.exit(1)