[Bug] transaction-pool unwrapping undefined.

[TarikGul]

While building out the extended e2e-tests, I was consistently getting this error:

2022-11-28 16:07:30 error: Cannot read properties of undefined (reading 'unwrap') 
 TypeError: Cannot read properties of undefined (reading 'unwrap')
    at NodeTransactionPoolService.computeExtPriority (/Users/tarikgul/Desktop/parity/tools-team/substrate-api-sidecar/build/src/services/node/NodeTransactionPoolService.js:89:80)
    at NodeTransactionPoolService.extractExtrinsicInfo (/Users/tarikgul/Desktop/parity/tools-team/substrate-api-sidecar/build/src/services/node/NodeTransactionPoolService.js:61:37)
    at processTicksAndRejections (node:internal/process/task_queues:96:5)
    at async Promise.all (index 0)
    at async NodeTransactionPoolService.fetchTransactionPool (/Users/tarikgul/Desktop/parity/tools-team/substrate-api-sidecar/build/src/services/node/NodeTransactionPoolService.js:35:26)
    at async NodeTransactionPoolController.getNodeTransactionPool (/Users/tarikgul/Desktop/parity/tools-team/substrate-api-sidecar/build/src/controllers/node/NodeTransactionPoolController.js:47:62)
    at async /Users/tarikgul/Desktop/parity/tools-team/substrate-api-sidecar/build/src/controllers/AbstractController.js:226:9

I was able to reproduce it, and it should be looked into and resolved.

This involved the following endpoint /node/transaction-pool?includeFee=true