bumping php 7.1 version to try to fix segfault

Author: weaverryan

.travis.yml

@@ -17,7 +17,7 @@ env:
 matrix:
     fast_finish: true
     include:
-        - php: 7.1
+        - php: 7.1.33
         - php: 7.3
         - php: 7.3
           env: MAKER_TEST_VERSION=dev