Fix issue 755 and typo in A18-1-1 test

Description

Fix issue #755 following suggestion therein.

[ ] Release or process automation (GitHub workflows, internal scripts)
[ ] Internal documentation
[ ] External documentation
[x] Query files (.ql, .qll, .qls or unit tests)
[ ] External scripts (analysis report or other code shipped as part of a release)

A change note (development_handbook.md#change-notes) is required for any pull request which modifies:

If you are only adding new rule queries, a change note is not required.

Author: Is a change note required?

🚨🚨🚨 Reviewer: Confirm that format of shared queries (not the .qll file, the .ql file that imports it) is valid by running them within VS Code.

Reviewer: Confirm that either a change note is not required or the change note is required and has been added.

For PRs that add new queries or modify existing queries, the following checklist should be completed by both the author and reviewer:

[x] Have all the relevant rule package description files been checked in?
[x] Have you verified that the metadata properties of each new query is set appropriately?
[x] Do all the unit tests contain both "COMPLIANT" and "NON_COMPLIANT" cases?
[x] Are the alert messages properly formatted and consistent with the style guide?
[ ] Have you run the queries on OpenPilot and verified that the performance and results are acceptable?
As a rule of thumb, predicates specific to the query should take no more than 1 minute, and for simple queries be under 10 seconds. If this is not the case, this should be highlighted and agreed in the code review process.
[x] Does the query have an appropriate level of in-query comments/documentation?
[x] Have you considered/identified possible edge cases?
[x] Does the query not reinvent features in the standard library?
[x] Can the query be simplified further (not golfed!)

[x] Have all the relevant rule package description files been checked in?
[x] Have you verified that the metadata properties of each new query is set appropriately?
[x] Do all the unit tests contain both "COMPLIANT" and "NON_COMPLIANT" cases?
[x] Are the alert messages properly formatted and consistent with the style guide?
[x] Have you run the queries on OpenPilot and verified that the performance and results are acceptable?
As a rule of thumb, predicates specific to the query should take no more than 1 minute, and for simple queries be under 10 seconds. If this is not the case, this should be highlighted and agreed in the code review process.
[x] Does the query have an appropriate level of in-query comments/documentation?
[x] Have you considered/identified possible edge cases?
[x] Does the query not reinvent features in the standard library?
[x] Can the query be simplified further (not golfed!)