Documentation: Add missing alternative for plugin in-tree testing

Bug: Issue 12096
Change-Id: Id24b167c53184868b076864f8d0543595bb7f040

src/main/resources/Documentation/build.md

diff --git a/src/main/resources/Documentation/build.md b/src/main/resources/Documentation/build.md
index aa04426..bf939f9 100644
--- a/src/main/resources/Documentation/build.md
+++ b/src/main/resources/Documentation/build.md
@@ -69,9 +69,10 @@
   ./tools/eclipse/project.py
 ```
 
-To execute the tests run:
+To execute the tests run either one of:
 
 ```
+  bazel test --test_tag_filters=@PLUGIN@ //...
   bazel test plugins/@PLUGIN@:@PLUGIN@_tests
 ```