requirementsWithStatusByTestPlan JQL function does not handle correctly the environment parameter

There are two problems:

1. the JQL function requirementsWithStatusByTestPlan() should handle correctly the Test Environment argument (3rd argument), where "" means "all environments" and "_NULL_" means empty environment

2. clicking on a bar of the overall coverage report, when the analysis is by test plan, produces an invalid JQL, with missing environment parameter

 
issueType in ("Epic", "Story", "Improvement", "Bug", "Technical task") and project = "XRAY" and fixVersion = "R2.3.0" and issue in requirementsWithStatusByTestPlan("OK","21148","false")