add origin to branch name

Author: MaxenceGollier

.github/workflows/jsobmarks.yml

@@ -48,13 +48,13 @@ jobs:
             gist_url = run_benchmarks(
               "${{ steps.sanitize.outputs.REPONAME }}",
               "benchmark",
-              reference_branch = "main",
+              reference_branch = "origin/${{ github.event.pull_request.base.ref }}",
             )
 
             run_solver_benchmarks(
               "${{ steps.sanitize.outputs.REPONAME }}",
               "benchmark",
-              reference_branch = "${{ github.event.pull_request.base.ref }}",
+              reference_branch = "origin/${{ github.event.pull_request.base.ref }}",
               gist_url = gist_url,
               script = "solver_benchmarks.jl",
             )