DOCSP-40402 fix Incorrect OS compatibility for Ops Manager 5 (#262)

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- [DOCSP-40402](https://jira.mongodb.org/browse/DOCSP-40402)
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Author: kanchana-mongodb

source/core/requirements.txt

@@ -411,7 +411,7 @@ Intel/AMD (``x86_64``) Hardware Architectures
      - 10, 11
 
    * - Red Hat Enterprise Linux / CentOS
-     - 7, 8, 9
+     - 7, 8
      - 7, 8, 9
 
    * - SUSE Linux Enterprise Server