[bug #59324] Erroneous values of rotation and scaling for some quads

[Sachin Kumar Singh]

Follow-up Comment #4, bug #59324 (project gnuastro):

task #15636 is already present for distortions. task #15798 is created for
making quads from multiple catalogs. 

For the results with reverse signs, I think I have an idea as to why they are
opposite. As we are calculating roatations w.r.t origin, it might be that some
vertices are matched in an opposite way than the rest of the vertices. 
For ex, in the given figure, D and D' are matched in a counter-clockwise
direction while the other 2 corresponding vertices are matched in clockwise
directions.

Now scale depends on X and cos(theta). As cos theta is an even function, it
won't change the sign and also the denominator of X is positive. Hence only
numerator of X which has x, y, ra, and dec can change the sign which is what I
think happens due to their corresponding positions. 

(file #50095)
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