**Steps to replicate the issue** (include links if applicable):
* Go to https://gerrit.wikimedia.org/r/c/mediawiki/extensions/Math/+/959303
* See CI error in example in: https://integration.wikimedia.org/ci/job/wmf-quibble-vendor-mysql-php74-docker/38379/console
* CI does not pass because of seeming redifinition of testUnderbrace function, although the function only one time occurs in code-base
```
17:46:01 Parse error: ./tests/phpunit/unit/TexVC/MMLRenderTest.php:36
17:46:01 34| }
17:46:01 35|
17:46:01 > 36| public function testUnderbrace() {
17:46:01 37| $input = "\underbrace{ a+b+\cdots+z }_{26}";
17:46:01 38| $mathMLtexVC = $this->generateMML( $input );Cannot redeclare MediaWiki\Extension\Math\Tests\TexVC\MMLRenderTest::testUnderbrace() in ./tests/phpunit/unit/TexVC/MMLRenderTest.php on line 36
```
**What happens?**:
CI checks do not pass
**What should have happened instead?**:
CI checks should pass without error