urequests: content: Use finally to close socket regardless of possible error.

urequests/urequests.py

@@ -16,7 +16,9 @@ class Response:
     @property
     def content(self):
         if self._cached is None:
+            try:
                 self._cached = self.raw.read()
+            finally:
                 self.raw.close()
                 self.raw = None
         return self._cached