Add Associate Engineer roles

Why is this change being made?

Engineering recently reinstated a grade 5 engineering role, renamed from junior to associate. This MR adds this level to existing job families.

Review app:

• Backend
• Frontend
• Fullstack

Changes in the compensation calculator and Workday have already been completed. This merge request updates the job families.

Note there is a separate issue for removing duplication in the Development Department job families Clean up job families for engineering IC and ma... (#9235 - closed)

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