update .dockerignore (#3540)
update .dockerignore (#3540)

Signed-off-by: Connor1996 <f7e3376ac32ecd54ff96995c24a9472cac06d4cb@gmail.com>
BusyJay/tikv,BusyJay/tikv,BusyJay/tikv,c4pt0r/tikv,pingcap/tikv,pingcap/tikv,BusyJay/tikv