Tesla TSLA.O surged 10.1%, while AT&T Inc T.N tumbled to bring down telecom shares after the wireless carrier cut its cash flow forecast saying some subscribers were delaying bill payments. By Echo Wang July 21 (Reuters) - The Nasdaq edged higher on Thursday boosted by gains in electric automaker Tesla on its better-than-expected quarterly results, which helped offset a slide in telecom and energy shares. Rising inflation also led the European Central Bank to belatedly join global peers in a rate-hike cycle with an aggressive 50-basis point increase.