Revert "Change test to use linked"

This reverts commit a90e6f5.

Author: penelopeysm

test/ad.jl

@@ -23,8 +23,7 @@ using DynamicPPL: LogDensityFunction
             varinfos = DynamicPPL.TestUtils.setup_varinfos(m, rand_param_values, vns)
 
             @testset "$(short_varinfo_name(varinfo))" for varinfo in varinfos
-                # TODO: This runs linked. Should we test unlinked as well?
-                varinfo = DynamicPPL.link(varinfo, m)
+                # TODO: This runs unlinked. Should we test linked as well?
                 f = LogDensityFunction(m, varinfo)
                 x = DynamicPPL.getparams(f)
                 # Calculate reference logp + gradient of logp using ForwardDiff
@@ -58,15 +57,14 @@ using DynamicPPL: LogDensityFunction
                             ref_ldf, adtype
                         )
                     else
-                        # TODO: Should we test unlinked as well?
-                        @test DynamicPPL.TestUtils.AD.run_ad(
+                        # TODO: Should we test linked as well?
+                        DynamicPPL.TestUtils.AD.run_ad(
                             m,
                             adtype;
-                            test=true,
-                            benchmark=true,
+                            linked=false,
                             varinfo=varinfo,
                             expected_value_and_grad=(ref_logp, ref_grad),
-                        ) isa Any
+                        )
                     end
                 end
             end