Issue 1698: Use safe_sleep executable in bash scripts (#1707)

* use safe_sleep executable in bash scripts

* new line at the end of safe_sleep bash script

* Replacing relative paths with absolute paths and changing location of safe_sleep

Co-authored-by: Ferenc Hammerl <31069338+fhammerl@users.noreply.github.com>

src/Misc/layoutroot/safe_sleep.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+
+SECONDS=0
+while [[ $SECONDS != $1 ]]; do
+    :
+done