Fix repo path and don't configure default branch

This ensures that the current PR branch is used

Author: cmnrd

.github/workflows/benchmark-tests.yml

@@ -12,7 +12,6 @@ on:
       benchmarks-ref:
         required: false
         type: string
-        default: main
 
 jobs:
   run:
@@ -21,7 +20,7 @@ jobs:
       - name: Check out benchmarks
         uses: actions/checkout@v3
         with:
-          repository: lf-lang/benchmarks
+          repository: lf-lang/benchmarks-lingua-franca
           ref: ${{ inputs.benchmarks-ref}}
       - name: Check out lingua-franca repository
         uses: actions/checkout@v3