This tests the basic functionality of the relayer, including: - Relaying from Subnet A to Subnet B - Relaying from Subnet B to Subnet A - Relaying an already delivered message - Setting StartBlockHeight in config.

This tests relaying a message manually provided in the relayer config.

Tests relayer support for off-chain Teleporter Registry updates - Configures the relayer to send an off-chain message to the Teleporter Registry - Verifies that the Teleporter Registry is updated.