Fix data deleted outside of time range

[jwilder]

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This fixes a case where data outside of the time range specified in a delete was deleted incorrectly.

Steps to repro:

> insert cpu value=1 0
> insert cpu value=1 1
> insert cpu value=1 2
> insert cpu value1=1 2
> insert cpu value1=1 3
> insert cpu value1=1 4
> select * from cpu
name: cpu
time value value1
---- ----- ------
0    1
1    1
2    1     1
3          1
4          1
> delete from cpu where time >= 0 and time <= 2
> select * from cpu
>

With this fix, it works correctly now:

> insert cpu value=1 0
> insert cpu value=1 1
> insert cpu value=1 2
> insert cpu value1=1 2
> insert cpu value1=1 3
> insert cpu value1=1 4
> delete from cpu where time >= 0 and time <= 2
> select * from cpu
name: cpu
time value value1
---- ----- ------
3          1
4          1

The issue was that if an earlier series (as seen by DeleteRange) was fully deleted, a faster path delete case was called with all series instead of the one.

Fixes #7706

[stuartcarnie]

LGTM 👍🏻