Add docs

Author: xrmx

instrumentation/opentelemetry-instrumentation-aiohttp-client/src/opentelemetry/instrumentation/aiohttp_client/__init__.py

@@ -84,6 +84,20 @@ def response_hook(span: Span, params: typing.Union[
 
    AioHttpClientInstrumentor().instrument(request_hook=request_hook, response_hook=response_hook)
 
+Exclude lists
+*************
+To exclude certain URLs from tracking, set the environment variable ``OTEL_PYTHON_AIOHTTP_CLIENT_EXCLUDED_URLS``
+(or ``OTEL_PYTHON_EXCLUDED_URLS`` to cover all instrumentations) to a string of comma delimited regexes that match the
+URLs.
+
+For example,
+
+::
+
+    export OTEL_PYTHON_AIOHTTP_CLIENT_EXCLUDED_URLS="client/.*/info,healthcheck"
+
+will exclude requests such as ``https://site/client/123/info`` and ``https://site/xyz/healthcheck``.
+
 API
 ---
 """