Remove now unused function test_dpkg_lock() (#5848)

automated install/basic-install.sh

@@ -388,28 +388,6 @@ os_check() {
     fi
 }
 
-# This function waits for dpkg to unlock, which signals that the previous apt-get command has finished.
-test_dpkg_lock() {
-    i=0
-    printf "  %b Waiting for package manager to finish (up to 30 seconds)\\n" "${INFO}"
-    # fuser is a program to show which processes use the named files, sockets, or filesystems
-    # So while the lock is held,
-    while fuser /var/lib/dpkg/lock >/dev/null 2>&1; do
-        # we wait half a second,
-        sleep 0.5
-        # increase the iterator,
-        ((i = i + 1))
-        # exit if waiting for more then 30 seconds
-        if [[ $i -gt 60 ]]; then
-            printf "  %b %bError: Could not verify package manager finished and released lock. %b\\n" "${CROSS}" "${COL_LIGHT_RED}" "${COL_NC}"
-            printf "       Attempt to install packages manually and retry.\\n"
-            exit 1
-        fi
-    done
-    # and then report success once dpkg is unlocked.
-    return 0
-}
-
 # Compatibility
 package_manager_detect() {