[BUG] - local tx submission is not backward compatible

**External**

**Summary**
I am using the local transaction submission mini protocol, while submitting a transaction that is built using Alonzo spec, and being submitted with era number 5 (Babbage), the node disconnects the connection and does not return an error message as well.

**Steps to reproduce**
Build an Alonzo era tx,
Prepare payload with era as `5`
Submit using the local transaction submission mini protocol

**Expected behaviour**
Since Babbage era tx spec is Alonzo compatible, a tx built using Alonzo only spec is a valid Babbage era tx. The protocol and node should accept the tx.