subscibeToConfirmedTransactions

**Is your feature request related to a problem? Please describe.**
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]
I want to be able to subscribe only to confirmed transactions just like how we are able to subscribe to mempool

**Describe the solution you'd like**
Just a new method to handle that

**Describe alternatives you've considered**
Using hiro chainhooks