fix: Bug in Session_Transaction_Manager::pop_transaction_id() fixed

[kidunot89]

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What does this implement/fix? Explain your changes.

• Fixes bug and improves error handling in Session_Transaction_Manager::pop_transaction_id

Thanks to @Shazamepool for identifying the bug and diversing the solution.

Does this close any currently open issues?

Resolves #844

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Where has this been tested?

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