cleanup: use regex to whitelist branches for CI

mmalerba · mmalerba · commit 257528f93dea · 2018-07-30T11:01:12.000-07:00
diff --git a/.travis.yml b/.travis.yml
@@ -18,13 +18,10 @@ addons:
 branches:
   only:
   - master
-  - 5.0.x
-  - 5.1.x
-  - 5.2.x
-  - 6.0.x
-  - 6.1.x
-  - 6.2.x
-  - 6.3.x
+  # 5.2.x, 6.0.x, etc
+  - /\d+\.\d+\.x/
+  # 5.x, 6.x, etc
+  - /\d+\.x/
 
 jobs:
   include:
