fix: use 5.0.1 till bpo is not more common

Signed-off-by: Barnabas Busa <barnabas.busa@ethereum.org>

Author: barnabasbusa

.github/workflows/_shared-run-test.yaml

@@ -46,7 +46,7 @@ on:
       kurtosis_branch:
         type: string
         description: "The branch name for the kurtosis ethereum package to use (default: )."
-        default: ""
+        default: "5.0.1"
       assertoor_tests:
         type: string
         description: "The list of assertoor test files to run."