Fix missing requirement for GUI test

Signed-off-by: Troy Lee <troy_lee@aspeedtech.com>
Change-Id: Ib71d67d2d52c591da8c154a595c0feefc0ed22dd
diff --git a/requirements.txt b/requirements.txt
index 8e1aaa3..0aa6f28 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -8,3 +8,7 @@
 click
 PyYAML>=5.1
 redfishtool
+robotframework-selenium2library
+webdrivermanager
+robotframework-angularjs
+robotframework-xvfb