By Dawn Chmielewski and Supantha Mukherjee (Reuters) – Spotify Technology SA on Wednesday promised high-margin returns from its costly expansion into podcasts and audiobooks as the audio streaming company hosted its first investor day since going public in 2018, hoping to stoke Wall Street’s enthusiasm despite the slowing global economy. Shares of the company jumped 6% in morning trade after losing 53% of its market value so far in 2022, worse than the 24% drop in the S&P 500 communication services sector index, which includes Spotify and other media and social network companies. “We are perfo…