celery tasks tests failing

[emdneto]

Describe your environment Describe any aspect of your environment relevant to the problem, including your Python version, platform, version numbers of installed dependencies, information about your cloud hosting provider, etc. If you're reporting a problem with a specific version of a library in this repo, please check whether the problem has been fixed on main.

tox -e py39-test-instrumentation-celery

>       self.assertEqual(
            event.attributes[SpanAttributes.EXCEPTION_TYPE], "CustomError"
        )
E       AssertionError: 'tests.celery_test_tasks.CustomError' != 'CustomError'
E       - tests.celery_test_tasks.CustomError
E       + CustomError

instrumentation/opentelemetry-instrumentation-celery/tests/test_tasks.py:128: AssertionError

Steps to reproduce
Describe exactly how to reproduce the error. Include a code sample if applicable.
Run tox -e py39-test-instrumentation-celery

What is the expected behavior?
Pass the tests

What is the actual behavior?
1 test failed

Additional context

Add capture the fully qualified type name for raised exceptions in spans (open-telemetry/opentelemetry-python#3837)