By Michael Tedder HBO Max is about to embark on a plan to bring its subscriber base into the triple digit millions. AT&T’s (T) – Get AT&T Inc. Report HBO Max launched two years ago during the summer, right as the world was starting to accept that the pandemic lockdown was going to be a long-term situation and people were grateful to have as much stuff to watch as possible. For years, HBO’s on demand service HBO Go enabled subscribers to watch the channel’s slate of original television series and specials, plus whichever films were being featured on the channel at the moment. But after AT&T acq…