tests: Add tests for the resource downloader

Change-Id: Ibc2685670dc50234b9b216226c03ed24c8bc9925
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/59089
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
1 file changed