As a user, I want a linear extrapolation of the lag-1 and lag-2 observations as a default WRES baseline

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Author Name: James (James)
Original Redmine Issue: 99442, https://vlab.noaa.gov/redmine/issues/99442
Original Date: 2021-12-08

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Given the need to compute skill relative to a linear extrapolation of the lag-1 and lag-2 observations for measures such as MSE
When I use WRES to achieve this
Then I should be able to select that baseline as a default baseline

Defined by Kitanidis and Bras (1980) as:

is the forecast corresponding to the straight line fitted to the two most recent measurements of the discharge Qob(i-j) and Qob(-i-j-1)

See #70419 for context and #70419-10 for the article.