Remove Travis references

Author: echarrod

.travis.yml

@@ -7,7 +7,7 @@
 ## Adding Features
 
 Any features added must be fully tested and documented, with examples supplied in the pull request.
-The feature must support the lowest Python version that the SDK supports (see [the travis file](.travis.yml) for all supported versions).  The feature
+The feature must support the lowest Python version that the SDK supports (see [the GitHub workflow tests file](./.github/workflows/tests.yaml) for all supported versions).  The feature
 must not introduce any unnecessary dependencies (although introducing a new third party library
 is open for discussion if absolutely required).
 

CONTRIBUTING.md

@@ -66,7 +66,7 @@ Yoti also allows you to enable user details verification from your mobile app by
 
 ## Requirements
 
-To see the versions of Python this SDK is compatible with, see the [.travis.yml](/.travis.yml) file.
+To see the versions of Python this SDK is compatible with, see the [the GitHub workflow tests file](./.github/workflows/tests.yaml) file.
 
 ## Installing the SDK