bpo-27640: Add --disable-test-modules configure option (GH-23886)

Added --disable-test-modules option to the configure script:
don't build nor install test modules.

Patch by Xavier de Gaye, Thomas Petazzoni and Peixing Xin.

Co-Authored-By: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Co-Authored-By: Xavier de Gaye <xdegaye@gmail.com>