Properly decode the aiohttp.ClientRequest body

The body of `aiohttp.ClientRequest` is a `aiohttp.payload.Payload` and
thus it won't compare correctly when used by the `BodyMatcher`.

`aiohttp.payload.Payload` provides a `decode` method we can use to turn
the underlying payload into a string representation suitable for
matching.

Author: hovsater

src/pook/interceptors/aiohttp.py

@@ -26,7 +26,7 @@ async def __call__(
         req = Request(
             method=request.method,
             headers=request.headers.items(),
-            body=request.body,
+            body=request.body.decode(),
             url=str(request.url),
         )
 

tests/integration/pook_aiohttp_test.py

@@ -0,0 +1,15 @@
+import pytest
+import aiohttp
+
+import pook
+
+pytestmark = [pytest.mark.pook]
+
+
+async def test_aiohttp_match_body():
+    body = {"foo": "bar"}
+    pook.post("http://example.com", body="foo=1").reply(200).json(body)
+    res = await aiohttp.ClientSession().post("http://example.com", data={"foo": 1})
+    assert res.status == 200
+    assert res.headers == {"Content-Type": "application/json"}
+    assert await res.json() == body