Doc: apt update perms

apt update requires sudo, keep consistency and restore copypasta-ability

README.md

@@ -66,7 +66,7 @@ There are prebuilt packages signed by a debian maintainer:
     sudo apt install curl sq
     curl -sSf https://apt.vulns.sexy/kpcyrd.pgp | sq dearmor | sudo tee /etc/apt/trusted.gpg.d/apt-vulns-sexy.gpg > /dev/null
     echo deb http://apt.vulns.sexy stable main | sudo tee /etc/apt/sources.list.d/apt-vulns-sexy.list
-    apt update
+    sudo apt update
 
 Docker