Use PHP 7.2 for test coverage

Author: sandrokeil

.travis.yml

@@ -21,12 +21,13 @@ matrix:
     env:
     - DEPENDENCIES=""
     - USE_VPACK=true
+    - EXECUTE_CS_CHECK=true
     - ARANGODB_VERSION=3.4.0
   - php: 7.2
     env:
     - DEPENDENCIES=""
     - USE_VPACK=false
-    - EXECUTE_CS_CHECK=true
+    - TEST_COVERAGE=true
     - ARANGODB_VERSION=3.4.0
   - php: 7.3
     env:
@@ -37,7 +38,6 @@ matrix:
     env:
     - DEPENDENCIES=""
     - USE_VPACK=false
-    - TEST_COVERAGE=true
     - ARANGODB_VERSION=3.4.0
   - php: nightly
     env: