User guide: Link code owners presentation from Gerrit Contributor Summit

Users might find it interesting to check out this presentation. Hence
make it easy to find it.

Signed-off-by: Edwin Kempin <ekempin@google.com>
Change-Id: I6d5253528003006a177a6c6f4fffd46ebdf86661

resources/Documentation/user-guide.md

diff --git a/resources/Documentation/user-guide.md b/resources/Documentation/user-guide.md
index 1471348..340d3a5 100644
--- a/resources/Documentation/user-guide.md
+++ b/resources/Documentation/user-guide.md
@@ -7,6 +7,11 @@
 This user guide explains the functionality of the `@PLUGIN@` plugin. For a
 walkthrough of the UI please refer to the [intro](how-to-use.html) page.
 
+**TIP:** You may also want to check out the [presentation about code
+owners](https://docs.google.com/presentation/d/1DupBnGr3apIx-jzxi9cHzSgkI-2c1ouGu1teQ4khSfc)
+from the [Gerrit Contributor Summit
+2020](https://docs.google.com/document/d/1WauJfNxracjBK3PxuVnwNIppESGMBtZwxMYjxxeDN6M).
+
 **NOTE:** How to setup the code owners functionality is explained in the
 [setup guide](setup-guide.html).