Test dependency updates (#25004)

* Upgrade pytest to 5.0.1

https://docs.pytest.org/en/latest/changelog.html#pytest-5-0-1-2019-07-04

* Upgrade asynctest to 0.13.0

* Upgrade requests_mock to 1.6.0

requirements_test.txt

@@ -1,7 +1,7 @@
 # linters such as flake8 and pylint should be pinned, as new releases
 # make new things fail. Manually update these pins when pulling in a
 # new version
-asynctest==0.12.3
+asynctest==0.13.0
 codecov==2.0.15
 coveralls==1.2.0
 flake8-docstrings==1.3.0
@@ -14,5 +14,5 @@ pytest-aiohttp==0.3.0
 pytest-cov==2.7.1
 pytest-sugar==0.9.2
 pytest-timeout==1.3.3
-pytest==5.0.0
-requests_mock==1.5.2
+pytest==5.0.1
+requests_mock==1.6.0

requirements_test_all.txt

@@ -2,7 +2,7 @@
 # linters such as flake8 and pylint should be pinned, as new releases
 # make new things fail. Manually update these pins when pulling in a
 # new version
-asynctest==0.12.3
+asynctest==0.13.0
 codecov==2.0.15
 coveralls==1.2.0
 flake8-docstrings==1.3.0
@@ -15,8 +15,8 @@ pytest-aiohttp==0.3.0
 pytest-cov==2.7.1
 pytest-sugar==0.9.2
 pytest-timeout==1.3.3
-pytest==5.0.0
-requests_mock==1.5.2
+pytest==5.0.1
+requests_mock==1.6.0
 
 
 # homeassistant.components.homekit