Fix incomplete assertions in tests realted to duplicated errors

Author: martosaur

test/logger_backend_test.exs

@@ -138,6 +138,7 @@ defmodule Sentry.LoggerBackendTest do
 
     :hackney.get("http://127.0.0.1:8003/error_route", [], "", [])
     assert_receive {^ref, _event}, 1000
+    assert_receive {^ref, _event}, 1000
   after
     Logger.configure_backend(Sentry.LoggerBackend, excluded_domains: [:cowboy, :bandit])
   end
@@ -151,6 +152,7 @@ defmodule Sentry.LoggerBackendTest do
 
     :hackney.get("http://127.0.0.1:8003/error_route", [], "", [])
     assert_receive {^ref, _event}, 1000
+    assert_receive {^ref, _event}, 1000
   after
     Logger.configure_backend(Sentry.LoggerBackend, excluded_domains: [:cowboy, :bandit])
   end

test/sentry/logger_handler_test.exs

@@ -117,6 +117,7 @@ defmodule Sentry.LoggerHandlerTest do
       :hackney.get("http://127.0.0.1:8003/error_route", [], "", [])
 
       assert_receive {^ref, _event}, 1000
+      assert_receive {^ref, _event}, 1000
     end
   end