Qiantong Zhong

Fix Flaky Tests

3

### Description Eleven tests were found to be flaky using [nondex](https://github.com/TestingResearchIllinois/NonDex): ``` org.apache.commons.jxpath.ri.compiler.ExtensionFunctionTest#testExpressionContext org.apache.commons.jxpath.ri.model.beans.BeanModelTest#testAxisDescendantOrSelf org.apache.commons.jxpath.ri.model.beans.BeanModelTest#testAxisParent org.apache.commons.jxpath.ri.model.beans.BeanModelTest#testAxisFollowing org.apache.commons.jxpath.ri.model.beans.BeanModelTest#testBooleanPredicate org.apache.commons.jxpath.ri.model.beans.BeanModelTest#testAxisDescendant org.apache.commons.jxpath.ri.model.beans.BeanModelTest#testAxisFollowingSibling org.apache.commons.jxpath.ri.model.dynabeans.DynaBeanModelTest#testAxisDescendantOrSelf org.apache.commons.jxpath.ri.model.dynabeans.DynaBeanModelTest#testAxisParent org.apache.commons.jxpath.ri.model.dynabeans.DynaBeanModelTest#testAxisFollowing org.apache.commons.jxpath.ri.model.dynabeans.DynaBeanModelTest#testAxisDescendant ``` The flakiness can be reproduced by...