Fix jit32 Perf testing

Fix jit32 Perf testing

In the CI, we were moving compatjit.dll into the Products directory
instead of the core_root directory, so the jit32 compatjit.dll was not
being picked up by the build. This change moves the nuget logic to before
we run runtest.cmd generatelayoutonly, so the jit32 compatjit.dll will be
moved to the core_root directory along with everything else.

Commit migrated from https://github.com/dotnet/coreclr/commit/b9694cd51ef165354e1fc2b856012cdc894ac1d5