BaseTools:The code used to test python module is moved to edksetup

BaseTools:The code used to test python module is moved to edksetup

BZ:https://bugzilla.tianocore.org/show_bug.cgi?id=1582

testing for presence of python modules should be done in edksetup
to reduce impact on subsequent build times.
This code currently exists in BaseTools/Tests/RunTest.py.

This patch is going to fix this issue.

Cc: Bob Feng <bob.c.feng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Signed-off-by: Zhiju.Fan <zhijux.fan@intel.com>
Reviewed-by: Bob Feng <bob.c.feng@intel.com>