Create standalone E2E test to test begin blocker

[chatton]

Summary

Currently we have a block of code in TestMsgTransfer_Succeeds_Nonincentivized which restarts the chain nodes and ensures begin blocker executes successfully.

We can no longer run this check when running tests in parallel, as this will stop chains that are expected to be running and interfere with other tests.

This check can be moved into a new test suite and have a single test which performs this check.

---

For Admin Use

• Not duplicate issue
• Appropriate labels applied
• Appropriate contributors tagged/assigned