Bump metric-registrar to 1.4.8

[ctlong]

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Description of the Change

Bump metric-registar to v1.4.8

Why Is This PR Valuable?

Bumps metric-registar to v1.4.8

Applicable Issues

None

How Urgent Is The Change?

Slightly less than urgent.

Other Relevant Parties

Consumers of the metric-registrar plugin

[moleske]

looks like it exists, merging