Bump x509-limbo and/or wycheproof in CI (#13020)

Co-authored-by: pyca-boringbot[bot] <pyca-boringbot[bot][email protected]>

Author: pyca-boringbot[bot]

.github/actions/fetch-vectors/action.yml

@@ -16,5 +16,5 @@ runs:
       with:
         repository: "C2SP/x509-limbo"
         path: "x509-limbo"
-        # Latest commit on the x509-limbo main branch, as of May 31, 2025.
-        ref: "90d7f1aa9fe32a485d5ac26fcfb4ca85415f6f4f" # x509-limbo-ref
+        # Latest commit on the x509-limbo main branch, as of Jun 01, 2025.
+        ref: "8ecc387ce7aa1c23811df007f0719c02b428f8ff" # x509-limbo-ref