build: fix execution-spec-tests sanitycheck URL (#31314)

Author: Halimao

build/checksums.txt

@@ -2,7 +2,7 @@
 
 # version:spec-tests [email protected]
 # https://github.com/ethereum/execution-spec-tests/releases
-# https://github.com/ethereum/execution-spec-tests/releases/download/pectra-devnet-6%40v1.0.0/fixtures_pectra-devnet-6.tar.gz
+# https://github.com/ethereum/execution-spec-tests/releases/download/pectra-devnet-6%40v1.0.0/
 b69211752a3029083c020dc635fe12156ca1a6725a08559da540a0337586a77e  fixtures_pectra-devnet-6.tar.gz
 
 # version:golang 1.24.1