Fixing Long-Flag Syntax and Missing Key-Path in txClient

[staheri14]

Problem

Due to recent changes in the Dockerfile for txsim, the txClient in the e2e tests fails to run because of incorrect syntax used for long flags and a missing option to specify the key path where the keyring is located.

Acceptance Criteria

Fix the mentioned issue and ensure e2e tests pass with no issue.

[rootulp]

Is this still a bug? The test-e2e CI task has been failing for a while but it's not clear to me if it's b/c of this or any of the other issues listed in #4028

[staheri14]

The concerns raised about the txclient in this issue, i.e.,

incorrect syntax used for long flags and a missing option to specify the key path

appear to have been addressed in the main branch. As the issue is no longer relevant, I’m closing it.