Refactored test code in parser_fragility_model_unittest, removed try/catch and used the context manager in all tests.
Refactored test code in parser_fragility_model_unittest, removed try/catch
and used the context manager in all tests.


Former-commit-id: b840e43604a13479817398e7fe9a032fd3d1dd45 [formerly f3fefad0e04e46fa6d19624125e20ffd2403be6d]
Former-commit-id: bb19031ccc25f5cf965f9ca17757a9cb5d88c038
gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine,gem/oq-engine