refactor: add more test file

data/tetests/spsolve_test.txt

-g1 = x1+3/3 * x2+ min(2,5)*x3 - 1;
-g2 = 1*3*x2 - 4*3;
-g3 = 1*3 * x2+sin(8-2)*x3 - 7;
-b = [0,0,0];
-r = sp_linsolvex([g1,g2,g3], b, [0,0,0], [x1,x2,x3]);
+a = sparse([0,0,0,1,2,2], [0,1,2,1,1,2], [1,1,2,3,3,sin(8-2)], 3, 3);
+b = [1,12,7];
+r = sp_linsolve(a, b, [0,0,0]);
 return r;
\ No newline at end of file

data/tetests/spsolvex_test.txt

+g1 = x1+3/3 * x2+ min(2,5)*x3 - 1;
+g2 = 1*3*x2 - 4*3;
+g3 = 1*3 * x2+sin(8-2)*x3 - 7;
+b = [0,0,0];
+r = sp_linsolvex([g1,g2,g3], b, [0,0,0], [x1,x2,x3]);
+return r;
\ No newline at end of file