Robust way of checking apt(-get) locks (#747)

Author: MatthijsBurgh

VERSION

@@ -1 +1 @@
-1.25.12
+1.25.13

installer/tue-install-impl.bash

@@ -959,7 +959,7 @@ function tue-install-system-now
         # Wait for apt-lock first (https://askubuntu.com/a/375031)
         i=0
         tput sc
-        while sudo fuser /var/lib/dpkg/lock >/dev/null 2>&1
+        while sudo fuser /var/{lib/{dpkg,apt/lists},cache/apt/archives}/{lock,lock-frontend} >/dev/null 2>&1
         do
             case $((i % 4)) in
                 0 ) j="-" ;;