NonRecordingSpan causes errors in wsgi

[codeboten]

The following error arises from the tracecontext integration tests in the core repo:

Traceback (most recent call last):
  File "/Users/alex.ianchici/workspace/opentelemetry-python/.tox/tracecontext/lib/python3.9/site-packages/flask/app.py", line 2464, in __call__
    return self.wsgi_app(environ, start_response)
  File "/Users/alex.ianchici/workspace/opentelemetry-python/.tox/tracecontext/src/opentelemetry-instrumentation-wsgi/instrumentation/opentelemetry-instrumentation-wsgi/src/opentelemetry/instrumentation/wsgi/__init__.py", line 339, in __call__
    if span.kind == trace.SpanKind.SERVER:
AttributeError: 'NonRecordingSpan' object has no attribute 'kind'

It appears the problem came from this change: 2f5bbc4