Modica Integration Tests

[stephenhand]

Description

In the integrationTestRunner, add support for the modica custom channel for the NZ staging and AS development accounts

Additional context

• Use the tests that currently exist for instagram as a pattern for implementing the modica tests
• The modica custom channel is implemented in https://github.com/techmatters/flex-plugins/tree/master/lambdas/account-scoped/src/customChannels/modica
• The chat script required to pass the test in NZ staging can be inferred from the lex v2 configuration found here: https://github.com/techmatters/flex-plugins/tree/master/twilio-iac/helplines/nz/configs/lex_v2/en_NZ,
• AS development will use the same script as the existing instagram test