Minor doc format changes

fit underlines to titles

Issue-ID: INT-1776

Signed-off-by: mrichomme <morgan.richomme@orange.com>
Change-Id: Iab6e38a5c41b3020e7731d5239f00269cd548108
diff --git a/docs/docs_usecases_release.rst b/docs/docs_usecases_release.rst
index 7450b6c..f5bf715 100644
--- a/docs/docs_usecases_release.rst
+++ b/docs/docs_usecases_release.rst
@@ -8,6 +8,7 @@
 
 Description
 -----------
+
 This session includes use cases and functional requirements which have been
 officially verified in Guilin release by the ONAP community.
 
@@ -21,9 +22,8 @@
      links to download the related assets and resources
   3. Known issues and workarounds
 
-
 Use cases
------------
+---------
 
 Guilin New Use Cases
 ~~~~~~~~~~~~~~~~~~~~
@@ -35,7 +35,7 @@
    :header-rows: 1
 
 Old Use Cases Tested in Guilin
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. csv-table:: use case table
    :file: ./files/csv/usecases-old-valid.csv
@@ -43,7 +43,6 @@
    :delim: ;
    :header-rows: 1
 
-
 Functional Requirements
 -----------------------
 
@@ -53,7 +52,6 @@
     :delim: ;
     :header-rows: 1
 
-
 Automated Use Cases
 -------------------