minor #46 Fixing tests for old PHPUnit versions (weaverryan)

This PR was merged into the master branch.

Discussion
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Fixing tests for old PHPUnit versions

There is an incorrect deprecation warning in an old version of PHPUnit. The PHPUnit Bridge 4.3 will fix this (by using a newer version of PHPUnit). To fix it for us, we can force PHP 7.1 to use a newer version.

Commits
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44333e0 Fixing tests

Author: weaverryan

.travis.yml

@@ -14,8 +14,9 @@ matrix:
     fast_finish: true
     include:
         - php: 7.1
+          env: SYMFONY_PHPUNIT_VERSION=7.4
         - php: 7.1
-          env: deps=high
+          env: deps=high SYMFONY_PHPUNIT_VERSION=7.4
         - php: 7.2
           env: deps=low
         - php: 7.3