Bump coveralls from 2.1.1 to 2.1.2

Bumps [coveralls](https://github.com/coveralls-clients/coveralls-python) from 2.1.1 to 2.1.2.
- [Release notes](https://github.com/coveralls-clients/coveralls-python/releases)
- [Changelog](https://github.com/coveralls-clients/coveralls-python/blob/master/CHANGELOG.md)
- [Commits](TheKevJames/coveralls-python@2.1.1...2.1.2)

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

requirements-dev.txt

@@ -1,5 +1,5 @@
 black==19.10b0
-coveralls==2.1.1
+coveralls==2.1.2
 ddt==1.4.1
 flake8-import-order==0.18.1
 pytest==5.4.3