Update json_schemer from 0.2.16 to 0.2.17

Why is this change being made?

json_schemer Gem 0.2.16, which was introduced in !72546 (merged), is blocking !75753 (closed) to upgrade Ruby from 2.7 to 3.0.

Replaces !75783 (closed)

Blocks !75753 (closed)

Author Checklist

• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per say-why-not-just-what
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