HPCC-12416 Regression suite run is creating temporary ecl file that is not cleaned up

Add code to close suite when Ctr-C (KeyboardInterrupt exception) raised
into runSuiteQ(), runSuite() and runSuiteP() methods

Add code to remove all remaining, temporary generated ECL file into suite
init() and close() methods

Signed-off-by: Attila Vamos <attila.vamos@gmail.com>