update travis config for laravel 7

Author: michaeldyrynda

.travis.yml

@@ -8,11 +8,17 @@ matrix:
     fast_finish: true
     include:
         - php: 7.2
-          env: ILLUMINATE_VERSION=6.0.*
+          env: ILLUMINATE_VERSION=6.*
         - php: 7.3
-          env: ILLUMINATE_VERSION=6.0.*
-        - php: 7.4snapshot
-          env: ILLUMINATE_VERSION=6.0.*
+          env: ILLUMINATE_VERSION=6.*
+        - php: 7.4
+          env: ILLUMINATE_VERSION=6.*
+        - php: 7.2
+          env: ILLUMINATE_VERSION=7.*
+        - php: 7.3
+          env: ILLUMINATE_VERSION=7.*
+        - php: 7.4
+          env: ILLUMINATE_VERSION=7.*
 
 before_install: travis_retry composer require "illuminate/database:${ILLUMINATE_VERSION}" "illuminate/events:${ILLUMINATE_VERSION}" --no-update -v