fix SC2155 delcare and assign seperately in build/common.sh
fix SC2155 delcare and assign seperately in build/common.sh

see: https://www.shellcheck.net/wiki/SC2155

lojies/kubernetes,soltysh/kubernetes,mosoft521/kubernetes,enj/kubernetes,jackfrancis/kubernetes,jackfrancis/kubernetes,jessfraz/kubernetes,ping035627/kubernetes,liggitt/kubernetes,MikeSpreitzer/kubernetes,warmchang/kubernetes,GulajavaMinistudio/kubernetes,thockin/kubernetes,kevin-wangzefeng/kubernetes,thockin/kubernetes,PiotrProkop/kubernetes,jsafrane/kubernetes,dims/kubernetes,k82cn/kubernetes,kevin-wangzefeng/kubernetes,kevin-wangzefeng/kubernetes,enj/kubernetes,jessfraz/kubernetes,jessfraz/kubernetes,dims/kubernetes,olivierlemasle/kubernetes,kevin-wangzefeng/kubernetes,dims/kubernetes,k82cn/kubernetes,deads2k/kubernetes,MikeSpreitzer/kubernetes,warmchang/kubernetes,olivierlemasle/kubernetes,k82cn/kubernetes,thockin/kubernetes,jsafrane/kubernetes,PiotrProkop/kubernetes,deads2k/kubernetes,MikeSpreitzer/kubernetes,kubernetes/kubernetes,ping035627/kubernetes,soltysh/kubernetes,matthyx/kubernetes,gnufied/kubernetes,deads2k/kubernetes,matthyx/kubernetes,jsafrane/kubernetes,k82cn/kubernetes,liggitt/kubernetes,warmchang/kubernetes,enj/kubernetes,lojies/kubernetes,liggitt/kubernetes,mosoft521/kubernetes,soltysh/kubernetes,mahak/kubernetes,soltysh/kubernetes,enj/kubernetes,gnufied/kubernetes,liggitt/kubernetes,ping035627/kubernetes,jessfraz/kubernetes,lojies/kubernetes,olivierlemasle/kubernetes,matthyx/kubernetes,GulajavaMinistudio/kubernetes,gnufied/kubernetes,kubernetes/kubernetes,jessfraz/kubernetes,kubernetes/kubernetes,PiotrProkop/kubernetes,soltysh/kubernetes,PiotrProkop/kubernetes,liggitt/kubernetes,warmchang/kubernetes,matthyx/kubernetes,GulajavaMinistudio/kubernetes,lojies/kubernetes,mosoft521/kubernetes,mahak/kubernetes,mahak/kubernetes,jackfrancis/kubernetes,mosoft521/kubernetes,ping035627/kubernetes,deads2k/kubernetes,kevin-wangzefeng/kubernetes,PiotrProkop/kubernetes,GulajavaMinistudio/kubernetes,thockin/kubernetes,MikeSpreitzer/kubernetes,mahak/kubernetes,jackfrancis/kubernetes,kubernetes/kubernetes,mahak/kubernetes,gnufied/kubernetes,olivierlemasle/kubernetes,mosoft521/kubernetes,dims/kubernetes,lojies/kubernetes,jackfrancis/kubernetes,GulajavaMinistudio/kubernetes,warmchang/kubernetes,deads2k/kubernetes,gnufied/kubernetes,thockin/kubernetes,jsafrane/kubernetes,MikeSpreitzer/kubernetes,dims/kubernetes,ping035627/kubernetes,jsafrane/kubernetes,olivierlemasle/kubernetes,enj/kubernetes,matthyx/kubernetes,k82cn/kubernetes,kubernetes/kubernetes