Bump aiohttp from 3.6.3 to 3.7.4

Bumps [aiohttp](https://github.com/aio-libs/aiohttp) from 3.6.3 to 3.7.4.
- [Release notes](https://github.com/aio-libs/aiohttp/releases)
- [Changelog](https://github.com/aio-libs/aiohttp/blob/master/CHANGES.rst)
- [Commits](aio-libs/aiohttp@v3.6.3...v3.7.4)

Signed-off-by: dependabot[bot] <support@github.com>

requirements.txt

@@ -1,7 +1,7 @@
 # Automatically generated by https://github.com/damnever/pigar.
 
 # C:\Users\leejiho\CleanerBot\src\cleaner.py: 7
-aiohttp == 3.6.3
+aiohttp == 3.7.4
 
 # C:\Users\leejiho\CleanerBot\src\main.py: 2,3
 discord.py == 1.5.1