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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

Any relevant logs, error output, GraphiQL screenshots, etc?

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Any other comments?

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Where has this been tested?

• WooGraphQL Version: …
• WPGraphQL Version: …
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