remove: 7.2 dev-master test

Author: Antonio Dal Sie

.travis.yml

@@ -25,8 +25,6 @@ matrix:
       env: LARAVEL='^6.0'
     - php: '7.2'
       env: LARAVEL='^7.0'
-    - php: '7.2'
-      env: LARAVEL='dev-master'
     - php: '7.3'
       env: LARAVEL='5.5.*'
     - php: '7.3'