Enable all Sphinx build warnings as errors

It also fixes several issues to pass the gate.
Please note that .. code-block :: json content must be json.

Issue-ID: DOC-798
Signed-off-by: Cédric Ollivier <cedric.ollivier@orange.com>
Change-Id: I38a751b67ab70a5ed5d61cdd49fe914c7b9270cd
diff --git a/docs/release-notes.rst b/docs/release-notes.rst
index 93844b8..12e485a 100755
--- a/docs/release-notes.rst
+++ b/docs/release-notes.rst
@@ -182,6 +182,7 @@
 | **Release date**                     | 2023 January 27                                        |
 |                                      |                                                        |
 +--------------------------------------+--------------------------------------------------------+
+
 Features
 --------
 3.2.1