[Go SDK] Remove boolean returned from relevant Counters and Lists methods

[markmandel]

I think the only case of this is in the Go SDK, but writing this in case I missed one.

https://pkg.go.dev/agones.dev/agones/sdks/go#Alpha.IncrementCounter - returns a (bool, error), make the return signature just error - the boolean isn't doing anything.

Also do the same on:

• DecrementCounter
• SetCounterCount,
• SetCounterCapacity,
• SetListCapacity,
• AppendListValue,
• DeleteListValue.

Thanks!

[markmandel]

FYI: @igooch

@Kalaiselvi84 - might be another good task for you.

[markmandel]

Just saw this covered more than a few methods on the Go SDK, so edited with a list.