Bump aiohttp from 3.8.5 to 3.8.6 in /libraries/botbuilder-adapters-slack (#2039)

Bumps [aiohttp](https://github.com/aio-libs/aiohttp) from 3.8.5 to 3.8.6.
- [Release notes](https://github.com/aio-libs/aiohttp/releases)
- [Changelog](https://github.com/aio-libs/aiohttp/blob/master/CHANGES.rst)
- [Commits](aio-libs/aiohttp@v3.8.5...v3.8.6)

---
updated-dependencies:
- dependency-name: aiohttp
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

libraries/botbuilder-adapters-slack/requirements.txt

@@ -1,4 +1,4 @@
-aiohttp==3.8.5
+aiohttp==3.8.6
 pyslack
 botbuilder-core==4.15.0
 slackclient