Use github action, remove travis, drop phpunit 4 support and support …

…PHP 8.0 (FriendsOfSymfony#125)

* Move CI from Travis to Github action

* Drop PHP 5.5.6 support and add PHP 8.0 support

* Update ci.yml

Merge pull request FriendsOfSymfony#120 from marekm4/fix-domain-check

[Security] Add exact check for domain and port

Merge pull request FriendsOfSymfony#105 from SebScoFr/master

Fixing HTTP status code definition

Merge pull request FriendsOfSymfony#103 from Nyholm/patch-1

Support for Symfony 4

Merge pull request FriendsOfSymfony#79 from kralos/jwt

Merge pull request FriendsOfSymfony#88 from luispabon/http-foundation-3

Allow Symfony HTTPFoundation 3.0

New release including:

- better scope handling
- introduced PSR-4

bumped up development branch version

Merge pull request FriendsOfSymfony#40 from FriendsOfSymfony/hotfix/g…

…rants-scope-validation-fix

Fixed possible scope validation error...

Merge pull request FriendsOfSymfony#38 from patrickli/default_scopes

Use null as the default supported_scopes value.