錯誤：google-chrome-stable-44.0.2403.157-1.x86_64.rpm 的公鑰沒有安裝
Fedora22 系統更新軟件包。出現：
warning: /var/cache/dnf/google-chrome-eb0d6f10ccbdafba/packages/google-chrome-stable-44.0.2403.157-1.x86_64.rpm: Header V4 DSA/SHA1 Signature, key ID 7fac5991: NOKEY
The downloaded packages were saved in cache till the next successful transaction.
You can remove cached packages by executing 'dnf clean packages'
錯誤：google-chrome-stable-44.0.2403.157-1.x86_64.rpm 的公鑰沒有安裝
主要原因是安裝的google-chrome包的公鑰沒有安裝。
解決方法：
dnf update -y --nogpgcheck
我們用選項 --nogpgcheck臨時跳過包簽名驗證。
參考：https://ask.fedoraproject.org/en/question/31116/how-do-i-install-unsigned-packages-using-yum/