Sandbox auth wizard: "Close" button actually is a "Cancel"/"Abort" button

*Steps:*

1. EXEC: In "OpenShift Application Explorer": pick "Login" in ctx menu to your cluster
2. ASSERT: connection wizard pops up
3. EXEC: hit link "Red Hat Developer" Sandbox
4. ASSERT: authentication wizard pops up (if it doesn't you may have to kill the existing session in Preferences JBoss Tools > OAuth > "Remove")
   
5. EXEC: Click "Close" button

*Result:*
The dialog is closed, authentication is aborted. Thus what the button does is aborting/cancelling the authentication. Labelling it "Cancel" or "Abort" would thus better match it's purpose.