Twenty-seven years ago, Laurie Coleman joined the Hong Kong Bach Choir. Today, as the choir prepares for its 50th anniversary concert, the English teacher, originally from Georgia in the United States, is its longest-serving member. Given their long involvement, Coleman wonders what her life in Hong Kong would have been like without it. “We moved here from Chicago in 1989 when my husband took a position with the music department at Hong Kong Baptist University. Five of the time came with….