Instrument `pg` connection, i.e. `client.connect()`

[mattfysh]

Currently the time taken to initialize a connection to the database is not instrumented, and is showing up as "Missing instrumentation" span immediately before the db query spans

[HazAT]

Can you create your own Span to measure this?
https://docs.sentry.io/platforms/node/performance/instrumentation/custom-instrumentation/
Also maybe the OTEL integration already does it
https://docs.sentry.io/platforms/node/performance/instrumentation/opentelemetry/