[NRRPLT-7946] Update dependencies. Use unittest.mock instead of PyPI mock

Change-Id: I418aff59ff1585622c142d495d3ed44d144608f3

hbp_nrp_virtual_coach/requirements.txt

 # third-party dependencies
 future
 texttable==0.8.7
-progressbar2==3.34.0
+progressbar2==3.52.1
 httplib2==0.12.1
 pandas==1.0.5
 jupyter==1.0.0

hbp_nrp_virtual_coach/requirements_extension_tests.txt

 #the following is required for the unit testing
-mock==1.0.1
\ No newline at end of file
+mock==1.0.1; python_version < "3.3"
\ No newline at end of file