Investigate and implement mocks in tests for better abstraction

[lumtis]

Different module message/state transition depends on other module interfaces.
Example: campaign's MsgInitializeMainnet creates a chain launch module

For better abstraction, we should investigate and work on mocking ability for messages and queries depending on other modules

• List all messages with external module dependency
• Specify mock implementation
• Create tasks accordingly for the different mocks and changes to make in tests. Sperate by messages or eventually by modules