### Body

We had an issue where extra link class (`AIPlatformConsoleLink`) was removed in [PR](https://github.com/apache/airflow/pull/26836) without removing the class from the `provider.yaml` extra links this resulted in web server exception as shown in https://github.com/apache/airflow/pull/28449


**The Task:**
Add validation that classes of extra-links in provider.yaml are importable

### Committer

- [X] I acknowledge that I am a maintainer/committer of the Apache Airflow project.
#
#
from __future__ import annotations
import json
import pathlib
import sys
import textwrap
from collections import Counter
from itertools import chain, product
from typing import Any, Iterable
import jsonschema
import yaml
from jsonpath_ng.ext import parse
from rich.console import Console
from tabulate import tabulate
try:
    from yaml import CSafeLoader as SafeLoader
except ImportError:
    from yaml import SafeLoader  
if __name__ != "__main__":
    raise Exception(
        "This file is intended to be executed as an executable program. You cannot use it as a module."
    )
ROOT_DIR = pathlib.Path(__file__).resolve().parents[3]