Bump boto3 from 1.13.16 to 1.13.19 (#1609)

Bumps [boto3](https://github.com/boto/boto3) from 1.13.16 to 1.13.19.
- [Release notes](https://github.com/boto/boto3/releases)
- [Changelog](https://github.com/boto/boto3/blob/develop/CHANGELOG.rst)
- [Commits](https://github.com/boto/boto3/compare/1.13.16...1.13.19)

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

requirements.txt

@@ -1,5 +1,5 @@
 adr==0.18.9
-boto3==1.13.16
+boto3==1.13.19
 imbalanced-learn==0.6.2
 joblib==0.15.1
 libmozdata==0.1.68