Assert stable connection pool metric names in stable semconv mode

[trask]

The HikariCP and Vibur connection-pool tests verify, after closing the data source, that pool metrics stop being emitted via waitAndAssertMetrics(..., isEmpty). The db.client.connection.count check already switches between the stable and old metric name based on emitStableDatabaseSemconv(), but the remaining post-close absence checks hardcoded the old db.client.connections.* names:

• HikariCP: idle.min, max, pending_requests
• Vibur: max

In stable mode the old-named metrics are never emitted, so those isEmpty assertions passed vacuously and never verified that the stable-named metric (db.client.connection.*) was actually unregistered after close.

This wraps those names in the same emitStableDatabaseSemconv() conditional already used for the count metric, matching the existing pattern in the c3p0 test (AbstractC3p0InstrumentationTest).

[Copilot]

Pull request overview

This PR fixes a gap in connection-pool metrics tests (HikariCP and Vibur) so that post-close “no more metrics emitted” assertions validate the correct metric names under stable database semconv mode (db.client.connection.*) instead of passing vacuously by checking only legacy names.

Changes:

• Update HikariCP post-close assertions to switch between stable (db.client.connection.*) and legacy (db.client.connections.*) metric names based on emitStableDatabaseSemconv().
• Update Vibur post-close max-connections assertion similarly to ensure stable-name metrics are actually asserted as absent after shutdown.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
instrumentation/hikaricp-3.0/testing/src/main/java/io/opentelemetry/instrumentation/hikaricp/AbstractHikariInstrumentationTest.java	Makes post-close “metrics are empty” assertions semconv-stability-aware for idle.min, max, and pending_requests.
instrumentation/vibur-dbcp-11.0/testing/src/main/java/io/opentelemetry/instrumentation/viburdbcp/AbstractViburInstrumentationTest.java	Makes post-close “max connections metric is empty” assertion semconv-stability-aware.