Add test scenarios to Test_Suites sheet

[vivek-dhayalan]

As part of Input sheet restructuring the first task would be is move the mapping between test scenarios & test suites from test scenarios sheet to test suites sheet.

The following would be task associated with the same:

1. Remove test_suite column from sheet test_scenarios
2. Add test_scenarios column to test_suites sheet

leave test_apis column in Test_Scenarios sheet as it is at the moment, we can change it after we fix this ticket.

This would also result in the way we access the context variables. For example, currently the variables are accessed by ${test_scenario_name.test_case_name.request/response}. When we re-define that the scenario can be executed multiple times, then the name spacing should also include the test suite name and the context map have to be saved accordingly.
If the test suite name is not mentioned, then by default the current test_suite will be referenced.