Testing updates and minor fixes to TX handler

[okanaganrusty]

Updates for Sologenic Issue #2

• What kind of change does this PR introduce? (Bug fix, feature, docs update, ...) Discussed with Reza to update the pop() and del() method signatures.

pop(queue: string): Promise<MQTX | boolean>
del(queue: string, id: string): Promise<boolean>

Updated test cases for redis, hash and sologenictxhandler test cases to peform some basic testing. An example AcccountSet transaction is being sent to the XRPL with the hash and redis queues.

Updated sologenictxhandler.ts to check item.data!.txJSON instead of item.txJSON which was throwing an exception and causing test cases to fail.

• Other information: All test cases passing

$ export NODE_TLS_REJECT_UNAUTHORIZED=0
$ npm run watch
...

14 tests passed [20:28:57]

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