[#1630] fix remove_if_exists not removing a file

src/bin/admin/tests/memfile_tests.sh.in

@@ -23,6 +23,7 @@ set -eu
 kea_admin="@abs_top_builddir@/src/bin/admin/kea-admin"
 kea_lfc="@abs_top_builddir@/src/bin/lfc/kea-lfc"
 
+# Clean up any files used in testing.
 clean_up() {
     remove_if_exists \
         "${config_file-}" \

src/lib/testutils/dhcp_test_lib.sh.in

@@ -551,9 +551,10 @@ get_reconfigs() {
     ${_GET_RECONFIG_ERRORS##*[! ]}
 }
 
+# Remove the given directories or files if they exist.
 remove_if_exists() {
-    while test ${#} -gt 1; do
+    while test ${#} -gt 0; do
-        if test -n "${1}"; then
+        if test -e "${1}"; then
             rm -rf "${1}"
         fi
         shift