build(deps): bump libmozdata from 0.2.15 to 0.2.16 in /bot (#3544)

Bumps [libmozdata](https://github.com/mozilla/libmozdata) from 0.2.15 to 0.2.16.
- [Release notes](https://github.com/mozilla/libmozdata/releases)
- [Commits](mozilla/libmozdata@v0.2.14...v0.2.16)

---
updated-dependencies:
- dependency-name: libmozdata
  dependency-version: 0.2.16
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Author: marco-c

bot/requirements.txt

@@ -1,7 +1,7 @@
 aiohttp<4
 gitpython==3.1.57
 influxdb==5.3.2
-libmozdata==0.2.15
+libmozdata==0.2.16
 PyGithub==2.8.1
 python-hglib==2.6.2
 pyyaml==6.0.3