pgAdmin 4 commit: Required mock package for python < 3.3.

Required mock package for python < 3.3.
It was required for the commit:
1208206bc0eca2d135469258e8a209b983e668be

Also, do not fetch the scenario-name, when it is not avaiable (but - use
default vaule as the stringified test-case itself).

Branch
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master

Details
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https://git.postgresql.org/gitweb?p=pgadmin4.git;a=commitdiff;h=903389d7b76046141c92a720e9e515cc4bb46274

Modified Files
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requirements.txt | 3 ++-
web/regression/runtests.py | 8 +++++---
2 files changed, 7 insertions(+), 4 deletions(-)