Bump ruamel-yaml from 0.16.9 to 0.16.10

Bumps [ruamel-yaml](https://sourceforge.net/p/ruamel-yaml/code/ci/default/tree) from 0.16.9 to 0.16.10.

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

requirements.txt

@@ -6,7 +6,7 @@ jsonschema==3.2.0
 kinto-http==10.7.0
 pyrsistent==0.15.7
 requests==2.22.0
-ruamel.yaml==0.16.9
+ruamel.yaml==0.16.10
 six==1.14.0
 Unidecode==1.1.1
 urllib3==1.25.8