Support JUnit test report which does not have `classname` (eslint/sasslint)
Description
GitLab doesn't support JUnit test report which does not have classname (eslint/sasslint). This is because each test case's key is generated with testcase classname (Class name) and testcase name (Description).
To illustrate the problem, this xml will generate only one test case (It should be two)
<testsuites>
<testsuite package="org.eslint" time="0" tests="2" errors="2" name="sass/components/footer/_footer.scss">
<testcase time="0" name="org.eslint.empty-line-between-blocks"><failure message="Space expected between blocks"><![CDATA[line 8, col 1, Error - Space expected between blocks (empty-line-between-blocks)]]></failure></testcase>
<testcase time="0" name="org.eslint.empty-line-between-blocks"><failure message="Space expected between blocks"><![CDATA[line 20, col 1, Error - Space expected between blocks (empty-line-between-blocks)]]></failure></testcase>
</testsuite>
</testsuites>