Note in 'Production Targets' section: Users are now informed about th…

…e necessity of obtaining the targets key, a prerequisite to proceed.

Signed-off-by: Camila Macedo <camila.macedo@foundries.io>

Co-authored-by: vkhoroz <vkhoroz@users.noreply.github.com>

source/reference-manual/ota/production-targets.rst

@@ -35,7 +35,9 @@ Waves allow Factory operators to control an exact time when devices see a new ve
 Performing a Production OTA
 ---------------------------
 
-A user should define a process to select CI builds which need to be delivered to production devices.
+A customer should define a process to select CI builds which need to be delivered to production devices.
+Every user performing production OTAs should generate their personal :ref:`offline TUF targets key <ref-offline-keys>` used to sign production targets.
+
 Let's assume a user selected a CI build version 42 as ready to be run in production.
 To start the production release process, a user would create a new wave using the below command::