[tools & instruments] Fix DB calls

[zaliqarosli]

Brief summary of changes

Similar PR to #8128, assign_missing_instruments and instruments themselves got missed in #8074

• Have you updated related documentation?

Testing instructions (if applicable)

1. On main branch, try running tools/assign_missing_instruments.php and see error.
2. On main branch, try to render and save instruments and see errors in error log
3. On PR branch, repeat both steps without getting any errors

Link(s) to related issue(s)

• Resolves # (Reference the issue this fixes, if any.)

[driusan]

do these need to be fixed in the latest release or just on main?

[zaliqarosli]

@driusan issue does exist on 24.1-release .. should i change branches?

[driusan]

yes, please.