[cluster-test] Fix broken dashboard link
[cluster-test] Fix broken dashboard link

Performance dashboard link was using an old URL and now matches reality.

Closes: #7156

libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core,libra/libra,aptos-labs/aptos-core