The client might not breakout on slow connections

When the connection is slow, or operation timeout is configured to pretty low value, the SDK might not leave the event loop in case, when lcb_wait() function is being used to execute IO operations. In this case, regardless that actual data operation has been completed, and user callback invoked, the library might have configuration update operation running, and will wait for its completion, even though it is not required to return control from lcb_wait() operation by default.

The issue is related to CCBC-948. Previously the check was only performed for retry queue, but in fact it also makes sense to do the same check for every KV connection, during pending requests detection cycle.

It is still possible to control behaviour of whether the library should wait for pending configuration updates before returning from lcb_wait(), "wait_for_config" connection string option or lcb_cntl(..., LCB_CNTL_WAIT_FOR_CONFIG, ...) can be used to check default behaviour (which is "false").