HPCC-11960 Regression suite Wild card oddity

Add fix to handle files without '.ecl' extension.

Signed-off-by: Attila.Vamos <attila.vamos@gmail.com>
Merge pull request #6612 from AttilaVamos/HPCC-11960-fix

HPCC-11960 Regression suite Wild card oddity

Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>