Flaky test TestClient/Close/AllowImplicitSessions fix (#1870)

Author: kprokopenko

internal/query/client.go

@@ -704,11 +704,13 @@ func createImplicitSessionPool(ctx context.Context,
 		pool.WithLimit[*Session](cfg.PoolLimit()),
 		pool.WithTrace[*Session](poolTrace(cfg.Trace())),
 		pool.WithCreateItemFunc(func(ctx context.Context) (_ *Session, err error) {
-			core := &sessionCore{
-				cc:     cc,
-				Client: c,
-				Trace:  cfg.Trace(),
-				done:   make(chan struct{}),
+			core := &implicitSessionCore{
+				sessionCore{
+					cc:     cc,
+					Client: c,
+					Trace:  cfg.Trace(),
+					done:   make(chan struct{}),
+				},
 			}
 
 			return &Session{

internal/query/implicit_session_core.go

@@ -0,0 +1,11 @@
+package query
+
+import "context"
+
+type implicitSessionCore struct {
+	sessionCore
+}
+
+func (s *implicitSessionCore) Close(context.Context) error {
+	return nil
+}