Update OWNERS, OWNERS_ALIASES and SECURITY_CONTACTS

Author: cblecker

OWNERS

@@ -1,6 +1,6 @@
 # See the OWNERS docs at https://go.k8s.io/owners
 
 approvers:
-  # TODO: in your repo created from this template, you should replace the
-  # github-admin-team with a list of project owners, see the doc linked above.
-  - github-admin-team
+- michelle192837
+- chases2
+- sig-testing-leads

OWNERS_ALIASES

@@ -1,14 +1,12 @@
 # See the OWNERS docs at https://go.k8s.io/owners#owners_aliases
 
 aliases:
-  # TODO: remove this alias, it will go stale in your repo, and in your repo
-  # you should have your own set of approvers (see OWNERS)
-  # in the original template repo, we must maintain this list to approve changes
-  # to the template itself
-  github-admin-team:
-    - cblecker
-    - fejta
-    - idvoretskyi
-    - mrbobbytables
-    - nikhita
-    - spiffxp
+  sig-testing-leads:
+    - BenTheElder
+    - alvaroaleman
+    - aojea
+    - cjwagner
+    - jbpratt
+    - michelle192837
+    - pohly
+    - xmcqueen

SECURITY_CONTACTS

@@ -10,4 +10,5 @@
 # DO NOT REPORT SECURITY VULNERABILITIES DIRECTLY TO THESE NAMES, FOLLOW THE
 # INSTRUCTIONS AT https://kubernetes.io/security/
 
-github-usernames-go-here
+michelle192837
+chases2