NullChecker tests not executed

[scompo]

Null checker tests not executed by maven on CI

[scompo]

• last travis build: https://travis-ci.org/scompo/utils/builds/10661040
• file: utils/src/test/java/com/github/scompo/utils/assertions/NullCheckerTests.java
• revision: cd109d9

[scompo]

To solve this issue just rename the file and class name from NullCheckerTests to NullCheckerTest

[scompo]

solved here cfe8c3e