Maintainership: Remove Sandeepa

Sandeepa has left the project. Thank you for all the work on OpenBMC!

Change-Id: I6e2a68f56a6730c93cbe5aaec8b5476700e574c2
Signed-off-by: Gunnar Mills <gmills@us.ibm.com>
diff --git a/OWNERS b/OWNERS
index 31f1618..c6527e7 100644
--- a/OWNERS
+++ b/OWNERS
@@ -33,7 +33,6 @@
 
 owners:
 - gmills@linux.vnet.ibm.com
-- sandeepa.singh@ibm.com
 
 reviewers:
 - kirankumarb@ami.com
@@ -45,9 +44,6 @@
 - name: Gunnar Mills
   email: gmills@linux.vnet.ibm.com
   discord: GunnarM
-- name: Sandeepa Singh
-  email: sandeepa.singh@ibm.com
-  discord: sandeepa.singh
 - name: Kirankumar Ballapalli
   email: kirankumarb@ami.com
   discord: kirankumarb