Force aiohttp version to 2.3.10 and aiohttp-cors version to 0.5.3

This is to fix build issue for Ubuntu 19.04 package on Launchpad.
Ref #1583 https://github.com/GNS3/gns3-gui/issues/2774

requirements.txt

@@ -1,6 +1,6 @@
 jsonschema==2.6.0
-aiohttp>=2.3.3,<2.4.0 # pyup: ignore
-aiohttp-cors>=0.5.3,<0.6.0 # pyup: ignore
+aiohttp==2.3.10
+aiohttp-cors==0.5.3
 yarl>=0.11
 Jinja2>=2.7.3
 raven>=5.23.0
@@ -9,3 +9,4 @@ zipstream>=1.1.4
 typing>=3.5.3.0 # Otherwise yarl fails with python 3.4
 prompt-toolkit==1.0.15
 async-timeout<3.0.0 # pyup: ignore; 3.0 drops support for python 3.4
+