Fix calculation of simple statistics of filtered logs

[peterfpeterson]

Change back the old behavior that the simple statistical measures were calculated from faked values and times. These are only temporary. This also fixes a bug where filteredValuesAsVector() and filteredTimesAsVector() weren't always returning the same length.

Further detail of work

You will see that there is two tests that were commented out that are now back.

To test:

# import mantid algorithms
from mantid.simpleapi import *

Load(Filename="HYS_13656-13658", OutputWorkspace="sum")  # in system test data
FilterByLogValue(InputWorkspace="sum", OutputWorkspace="sum", LogName="s1", MinimumValue=0, MaximumValue=24.5, LogBoundary="Left")
runObj = mtd['sum'].run()
print(f"min={runObj.getStatistics('s1').minimum} max={runObj.getStatistics('s1').maximum}")

Where the minimum value is no longer negative even though FilterByLogValue was configure to remove negative values.

Refs #34794

This does not require release notes because it is already covered in a previous set of release notes.

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