Second City Capital Partners has formed a real estate investment trust that expects to include in its portfolio the City Center office complex in downtown St. Petersburg. Last year, Second City Capital was part of a joint venture that acquired the property at 150 2nd Ave. S. for $20 million. The Class A property includes a 12-story office tower and a four-story office building, connected by an atrium. City Office REIT Inc., in a filing with the SEC, says that upon completion of its initial public…