[Python] Add Sourabh and Sreenithi to Python triage (#37192)

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.github/ISSUE_TEMPLATE/bug_report_python.md

@@ -5,6 +5,8 @@ labels: kind/bug, priority/P2, lang/Python
 assignees:
   - gnossen
   - XuanWang-Amos
+  - sreenithi
+  - sourabhsinghs
 
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.github/ISSUE_TEMPLATE/feature_request_python.md

@@ -5,6 +5,8 @@ labels: kind/enhancement, priority/P2, lang/Python
 assignees:
   - gnossen
   - XuanWang-Amos
+  - sreenithi
+  - sourabhsinghs
 
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