[thci] conditionally import paramiko and change getting joiner state method (#3165)
[thci] conditionally import paramiko and change getting joiner state method (#3165)


srickardti/openthread,librasungirl/openthread,openthread/openthread,erja-gp/openthread,lanyuwen/openthread,srickardti/openthread,erja-gp/openthread,srickardti/openthread,LeZhang2016/openthread,lanyuwen/openthread,LeZhang2016/openthread,bukepo/openthread,chshu/openthread,turon/openthread,jwhui/openthread,LeZhang2016/openthread,gandreello/openthread,erja-gp/openthread,LeZhang2016/openthread,gandreello/openthread,lanyuwen/openthread,openthread/openthread,chshu/openthread,srickardti/openthread,lanyuwen/openthread,bukepo/openthread,erja-gp/openthread,bukepo/openthread,abtink/openthread,turon/openthread,chshu/openthread,jwhui/openthread,openthread/openthread,turon/openthread,erja-gp/openthread,chshu/openthread,jwhui/openthread,erja-gp/openthread,abtink/openthread,librasungirl/openthread,gandreello/openthread,gandreello/openthread,lanyuwen/openthread,gandreello/openthread,abtink/openthread,LeZhang2016/openthread,turon/openthread,chshu/openthread,abtink/openthread,openthread/openthread,jwhui/openthread,bukepo/openthread,lanyuwen/openthread,librasungirl/openthread,chshu/openthread,librasungirl/openthread,gandreello/openthread,LeZhang2016/openthread