Add moments_varendo to fs2000 unit test

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tests/fs2000/fs2000.mod

@@ -72,4 +72,4 @@ varobs gp_obs gy_obs;
 
 options_.solve_tolf = 1e-12;
 
-estimation(order=1,datafile=fsdat_simul,nobs=192,loglinear,mh_replic=2000,mh_nblocks=2,mh_jscale=0.8);
+estimation(order=1,datafile=fsdat_simul,nobs=192,loglinear,mh_replic=2000,mh_nblocks=2,mh_jscale=0.8,moments_varendo,consider_only_observed);