Add env PHP 7.4 to .travis.yml

vuongxuongminh · vuongxuongminh · commit 6e8f22c91e6a · 2020-06-25T23:32:13.000+07:00
diff --git a/.travis.yml b/.travis.yml
@@ -4,6 +4,7 @@ php:
     - 7.1
     - 7.2
     - 7.3
+    - 7.4
 
 install:
     - composer self-update
