Update sig-testing info in sigs.yaml

Corrected leads, meeting time, uri

sigs.yaml

@@ -535,15 +535,18 @@ sigs:
     leads:
     - name: Aaron Crickenberger
       github: spiffxp
-      company: Samsung
-    - name: Jeff Grafton
-      github: ixdy
+      company: Samsung SDS
+    - name: Erick Feja
+      github: fejta
       company: Google
+    - name: Timothy St. Clair
+      github: timothysc
+      company: Heptio
     meetings:
     - day: Tuesday
-      utc: "16:30"
+      utc: "20:00"
       frequency: weekly
-    meeting_url: https://zoom.us/j/553910341
+    meeting_url: https://zoom.us/j/2419653117
     meeting_archive_url: https://docs.google.com/document/d/1z8MQpr_jTwhmjLMUaqQyBk1EYG_Y_3D4y4YdMJ7V1Kk
     contact:
       slack: sig-testing