UniqueId attempted to provide an ordered unique id by using a nanosecond
timestamp, but doesn't take into account that time is not monotonic
increasing. This provides an implementation that will always be
increasing.
This means that two resources created by the same rule will get names
which sort in the order they are created.
The rest of the ID is still random base32 characters; we no longer set
the bit values that denote UUIDv4.
The length of the ID returned by PrefixedUniqueId is not changed by this
commit; that way we don't break any resources where the underlying
resource has a name length limit.
Fixes#8143.
James Bardin