Removing outdated STS code owners and adding one that was missing

Bug: 197237705
Test: code management CL. No expected test impact.
Change-Id: Ic0bb0a3a9a499d2711ea4845ff2e7fda4d35de69
diff --git a/hostsidetests/securitybulletin/OWNERS b/hostsidetests/securitybulletin/OWNERS
index 056fbe6..5e566ca 100644
--- a/hostsidetests/securitybulletin/OWNERS
+++ b/hostsidetests/securitybulletin/OWNERS
@@ -1,6 +1,5 @@
 # Bug component: 36824
-mspector@google.com
-manjaepark@google.com
+musashi@google.com
 cdombroski@google.com
 lgallegos@google.com
 hubers@google.com