release method
Implementation
void release(LockGrant grant) {
final lock = _locks[grant.table];
if (lock == null) return;
if (grant.mode == LockMode.read) {
lock.readers = (lock.readers - 1).clamp(0, 999999);
if (lock.readers == 0) lock.notifyNext();
} else {
lock.exclusive = false;
lock.notifyAll();
}
}