Update repository URL in the documentation

TF-A and TF-A Tests git repositories are getting moved to a TF-A/
namespace in order to easily identify what repos are for TF-A or TF-M.

Change-Id: Id3e9ae299fa4e0dd8699c967879cd8ce5a17c940
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
diff --git a/docs/user-guide.rst b/docs/user-guide.rst
index 546b6bc..c8cb53a 100644
--- a/docs/user-guide.rst
+++ b/docs/user-guide.rst
@@ -48,7 +48,7 @@
 
 ::
 
-    git clone https://git.trustedfirmware.org/tf-a-tests.git
+    git clone https://git.trustedfirmware.org/TF-A/tf-a-tests.git
 
 Building TF-A Tests
 -------------------