Update the build instructions to Bazel

The instructions were still explaining how to build with Buck.

Change-Id: Ib594f0dba5fed1d6faeaa779713f83bdf596b541

src/main/resources/Documentation/build.md

diff --git a/src/main/resources/Documentation/build.md b/src/main/resources/Documentation/build.md
index 4d8a0c3..cfe140f 100644
--- a/src/main/resources/Documentation/build.md
+++ b/src/main/resources/Documentation/build.md
@@ -1,16 +1,16 @@
 Build
 =====
 
-This plugin is built using Buck.
+This plugin is built in the Gerrit source tree using Bazel.
 
 
-Buck
+Bazel
 ----
 
-From gerrit source directory:
+From the plugin source directory:
 
 ```
-buck build plugins/avatars-external
+bazel build avatars-external
 ```
 
-You will find the `avatars-external.jar` file in `buck-out/gen/plugins/avatars-external`.
+You will find the `avatars-external.jar` file in `../../bazel-bin/plugins/avatars-external/avatars-external.jar`.