refactor: add support for multiple events of same type in AssertEvents

[crodriguezvega]

Description

This comment by @damiannolan got me thinking if we could use the AssertEvents (cc: @Anmol1696) function to standardize a bit the way we test events, so I tried to implement a way to be able to assert multiple events of the same type... Looking forward to feedback; happy to close the PR this is not useful.

At the moment there's one thing that I think it's not working properly, but I will comment on the code.

closes: #XXXX

Commit Message / Changelog Entry

refactor: add support for multiple events same type in assert events

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[damiannolan]

I wonder if we need this type, its kind of complex. I would probably opt for just using the sdk.Events type.
Can't we just write the events assertion like this:

events := res.GetEvents()
expected := sdk.Events{
	sdk.NewEvent(
		types.EventTypeDistributeFee,
		sdk.NewAttribute(types.AttributeKeyReceiver, suite.chainA.SenderAccount.GetAddress().String()),
		sdk.NewAttribute(types.AttributeKeyFee, defaultRecvFee.String()),
	),
	sdk.NewEvent(
		types.EventTypeDistributeFee,
		sdk.NewAttribute(types.AttributeKeyReceiver, suite.chainA.SenderAccount.GetAddress().String()),
		sdk.NewAttribute(types.AttributeKeyFee, defaultAckFee.String()),
	),
	sdk.NewEvent(
		types.EventTypeDistributeFee,
		sdk.NewAttribute(types.AttributeKeyReceiver, suite.chainA.SenderAccount.GetAddress().String()),
		sdk.NewAttribute(types.AttributeKeyFee, defaultTimeoutFee.String()),
	),
}

for _, evt := range expected {
	suite.Require().Contains(events, evt)
}

[crodriguezvega]

Great idea! Much simpler! :) I guess we don't need AssertEvents anymore then... I will refactor that in a following PR.

[Anmol1696]

Makes sense. The only reason to have something like a map is to have an easy to read expected values with less boiler plate, because all attribute keys and values are basically only strings.