offline endpoints not working

[mobeen-10]

Following endpoints are not working in offline mode are returning Internal Server Error.

1. /construction/payload
2. /construction/parse

1. Calling payload endpoint:
   It shows error in line:
   https://github.com/vechain/rosetta/blob/master/src/controllers/construction.ts#L663
   Cannot read properties of undefined (reading chainTag)

2. Calling parse endpoint:
   It shows error in line:
   https://github.com/vechain/rosetta/blob/master/src/controllers/construction.ts#L425
   Cannot read properties of undefined (reading baseGasPrice)

[moglu2017]

These bugs have been fixed.