improve: add ProposalExecuted event

[pemulis]

Signed-off-by: John Shutt pemulis@users.noreply.github.com

Motivation

We want a ProposalExecuted event tied to the original proposal time to make it easier for the Snapshot interface to determine whether a specific proposal was executed, and differentiate between duplicate transaction bundles that were created at different times.

Summary

Adds a ProposalExecuted event that includes the proposal hash and the proposal time, which triggers on completion of the executeProposal function.

Details

For the V2 version of the contract, we should consider adding proposalTime to other events like TransactionExecuted and ProposalDeleted. To keep this PR limited, I did not alter those events.

Testing

Check a box to describe how you tested these changes and list the steps for reviewers to test.

• Ran end-to-end test, running the code as in production
• New unit tests created
• Existing tests adequate, no new tests required
• All existing tests pass
• Untested

Issue(s)

Fixes #XXXX

[mrice32]

LGTM!

[chrismaree]

LGTM. let's get this in.

[chrismaree]

This is no longer relevent.