[chore] Pass runCtx into supervisor Health check test (#43681)

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Ex. Adding a feature - Explain what this achieves.-->
#### Description

Without a valid `runCtx`, anything that attempts to use the context
segfaults. In
open-telemetry/opentelemetry-collector#14058 I
am using the context, so this test borks. This adds the runCtx to fix
it.

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#### Link to tracking issue
open-telemetry/opentelemetry-collector#14058

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#### Testing

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#### Documentation

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Signed-off-by: sinkingpoint <[email protected]>

Author: sinkingpoint

cmd/opampsupervisor/supervisor/supervisor_test.go

@@ -2189,6 +2189,7 @@ func TestSupervisor_HealthCheckServer(t *testing.T) {
 
 	t.Run("Health check server errors out if port is in-use", func(t *testing.T) {
 		newSupervisor := &Supervisor{
+			runCtx:            t.Context(),
 			telemetrySettings: newNopTelemetrySettings(),
 			persistentState:   &persistentState{InstanceID: testUUID},
 			cfgState:          &atomic.Value{},