Remove post installation message from RPM packages

[f-galland]

Description

A message is printed to stdout after rpm package installation that references OpenSearch services and documentation.

[root@alma8 ~]# rpm -i wazuh-indexer-4.9.0-1_x86_64_94c91956b14.rpm 
### NOT starting on installation, please execute the following statements to configure opensearch service to start automatically using systemd
 sudo systemctl daemon-reload
 sudo systemctl enable opensearch.service
### You can start opensearch service by executing
 sudo systemctl start opensearch.service
### Create opensearch demo certificates in /etc/wazuh-indexer/
 See demo certs creation log in /var/log/wazuh-indexer/install_demo_configuration.log
### Upcoming breaking change in packaging
 In a future release of OpenSearch, we plan to change the permissions associated with access to installed files
 If you are configuring tools that require read access to the OpenSearch configuration files, we recommend you add the user that runs these tools to the 'opensearch' group
 For more information, see https://github.com/opensearch-project/opensearch-build/pull/4043

Tasks:

• Change the message to include a short summary on how to start the Wazuh Indexer service.