build: Add missing dashes in .travis.yml (restore PHP 7.1/7.2 tests)

Follows-up f638c599d5, in which I accidentally removed the leading
dashes from the entries in the 'include' array.

Apparently when you do that, it just assumes you intended to
have a dash in front of the first line and create a single-item
object in which you have the same key four times, where the last
one wins. Thus, testing only 1 variant: php 7.0.

Change-Id: I3fd77749017d15cc60daf9a531417b55c604e7ff

diff --git a/.travis.yml b/.travis.yml
index ebe1631..bf905e0 100644 (file)
--- a/.travis.yml
+++ b/.travis.yml
@@ -24,10 +24,10 @@ cache:
 matrix:
   fast_finish: true
   include:
-      php: 7.3
-      php: 7.2
-      php: 7.1
-      php: 7
+    - php: 7.3
+    - php: 7.2
+    - php: 7.1
+    - php: 7
   allow_failures:
     - php: 7.3