Bump ecdsa from 0.13.2 to 0.13.3

Bumps [ecdsa](https://github.com/warner/python-ecdsa) from 0.13.2 to 0.13.3.
- [Release notes](https://github.com/warner/python-ecdsa/releases)
- [Changelog](https://github.com/warner/python-ecdsa/blob/master/NEWS)
- [Commits](tlsfuzzer/python-ecdsa@python-ecdsa-0.13.2...python-ecdsa-0.13.3)

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

requirements.txt

@@ -51,7 +51,7 @@ decorator==4.4.0
 Deprecated==1.2.6
 docker==4.0.2
 # docutils==0.15.2  # Disabled due to build conflict and GPL
-ecdsa==0.13.2
+ecdsa==0.13.3
 elasticsearch-dsl==7.0.0
 elasticsearch==7.0.4
 enum34==1.1.6