Adding duplicate-finder script (#2550)

* Adding duplicate-finder script
* removing unused constant and updated doctstring

scripts/find_duplicated_names.sh

@@ -0,0 +1,25 @@
+#!/bin/bash
+
+# This script will find all duplicated names in the Kanidm database, handy for upgrading from 1.1.0 RC15 to RC16
+
+if [ -z "${KANIDM_NAME}" ]; then
+    echo "Setting the KANIDM_NAME env var will save you selecting a user multiple times!" >&2
+fi
+
+RES="$(
+	kanidm group list | grep -E '^name' | awk '{print $2}' || exit 1
+	kanidm person list | grep -E '^name' | awk '{print $2}' || exit 1
+	kanidm service-account list | grep -E '^name' | awk '{print $2}' || exit 1
+	kanidm system oauth2 list | grep -E '^oauth2_rs_name' | awk '{print $2}' || exit 1
+)"
+
+DUPES="$(echo "${RES}" | sort | uniq -c | grep -vE '^\s+1' | awk '{print $2}')"
+
+if [ -z "${DUPES}" ]; then
+    echo "No duplicates found" >&2
+    exit 0
+else
+    echo "Duplicates found, here's a list" >&2
+    echo "${DUPES}"
+    exit 1
+fi