Cross link new dashboard on the old dashboard

[elenahoo]

Raised by @tkstanczak https://dashboard.flashbots.net/ is still available
it should either display clearly information that the data is for PoW Ethereum before the Merge
then it should display a very visible link to the new transparency.flashbots.net website
OR should automatically redirect to transparency.flashbots.net
Why:
when I search transparency flashbots in Google, a link to the old dashboard is displayed first