Minor improvement

mehrshaddarzi · mehrshaddarzi · commit 14fa1dec36be · 2020-02-07T12:21:00.000+03:30
diff --git a/.travis.yml b/.travis.yml
@@ -1,12 +1,15 @@
 language: php
 
+os:
+  - linux
+
 php:
   - 5.6
   - 7.2
   - 7.3
   - 7.4
 
-brfore_install:
+before_install:
   - composer install
 
 script:
