[Glean] Migrate TermsOfUseTelemetry to use the GleanWrapper instead

:rocket: Context

TermsOfUseTelemetry is recording telemetry events with the concrete Glean implementation. We don't want this anymore. More on telemetry tests here.

:memo: Description

• Use the GleanWrapper inside TermsOfUseTelemetry and replace calls to each GleanMetrics. with the corresponding API.
• TermsOfUseTelemetryTests should be adjusted so we pass a MockGleanWrapper and assert accordingly.

:information_source: Reference Person

lmarceau

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