[BLUEJ-1276] "Run Tests" button isn't disabled when "Test All" in menu is selected

"Run Tests" button isn't disabled when "Test All" in menu is selected, this shows when a breakpoint is set and the debugger is at the breakpoint. I suppose the button actually never disable but when no breakpoint is set we don't have time to notice that when tests are fast to run.

---

Issue metadata

• Issue type: Bug
• Priority: Medium