Fixed a build issue on Mac OS

This fixes an issue that was happening with ForceBalance Travis CI builds on Mac OS:

make[4]: *** No rule to make target -lz', needed by _work_queue.so'. Stop.

To fix this issue, -lz was removed from EXTERNAL_DEPENDENCIES in work_queue/src/bindings/python3/Makefile and added to python_ldflags and python3_ldflags in configure.

Release with fixed issue with Swig 4

This release contains updates that solves the compilation issue with swig 4

Release with fixed Python 3.7 binding

This is a special release based on version 7.0.10 with work_queue Python 3.7 binding fixed