IDistributedLockProvider for Redis won't acquire lock when using multiple databases #240

Given:

        var connectionPoolManager = services.BuildServiceProvider().GetService<IRedisConnectionPoolManager>()
                                    ?? new RedisConnectionPoolManager(connectionConfiguration);
        var dbs = connectionPoolManager.GetConnections().Select(c => c.GetDatabase());

This wont work (handle returns null always - no exception thrown):
services.AddSingleton<IDistributedLockProvider>(_ => new RedisDistributedSynchronizationProvider(dbs);
But this does work:

services.AddSingleton<IDistributedLockProvider>(_ => new RedisDistributedSynchronizationProvider(dbs.First()));

Cool library btw - Thanks!