Arrakis raises $38M from Blossom and Accel, with Datadog CEO and OpenAI exec joining the round London-based Arrakis emerged from stealth with $38 million raised over six months, including a $30 million round led by Blossom and Accel, with Datadog CEO and an OpenAI executive joining as investors. London-based Arrakis has come out of stealth with $38 million raised over six months, including a $30 million…