I suddenly experienced this error, and the solution for me was to disable to run tests in parallel.
Your milage may vary, since I could lower number of failing tests by configuring surefire to run parallel tests by ´classes´.:
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.22.2</version>
<configuration>
<parallel>classes</parallel>
<threadCount>10</threadCount>
</configuration>
</plugin>
As I wrote first, this was not enough for my test suite, so I completely disabled parallel by removing the <configuration>
section.