Add initial admin password prompt to OpenSearch service

[tcampbPPU]

Spinning up OpenSearch running takeout enable opensearch using all the default prompts results in the following crash from docker:

snapshot of logs:

Enabling OpenSearch Security Plugin
Enabling execution of install_demo_configuration.sh for OpenSearch Security Plugin 
OpenSearch 2.12.0 onwards, the OpenSearch Security Plugin a change that requires an initial password for 'admin' user. 
Please define an environment variable 'OPENSEARCH_INITIAL_ADMIN_PASSWORD' with a strong password string. 
If a password is not provided, the setup will quit. 
 For more details, please visit: https://opensearch.org/docs/latest/install-and-configure/install-opensearch/docker/
### OpenSearch Security Demo Installer
### ** Warning: Do not use on production or public reachable systems **
OpenSearch install type: rpm/deb on Linux 6.12.10-orbstack-00297-gf8f6e015b993 aarch64
OpenSearch config dir: /usr/share/opensearch/config/
OpenSearch config file: /usr/share/opensearch/config/opensearch.yml
OpenSearch bin dir: /usr/share/opensearch/bin/
OpenSearch plugins dir: /usr/share/opensearch/plugins/
OpenSearch lib dir: /usr/share/opensearch/lib/
Detected OpenSearch Version: 3.0.0-alpha1
Detected OpenSearch Security Version: 3.0.0.0-alpha1
No custom admin password found. Please provide a password via the environment variable OPENSEARCH_INITIAL_ADMIN_PASSWORD.

According to their docs

Note for OpenSearch 2.12 or later: Fresh installs of 2.12 or later require that you define an admin password — using the OPENSEARCH_INITIAL_ADMIN_PASSWORD environment variable — when configuring the security demo. For more information, see Setting up a demo configuration.

This PR just introduces another additional prompt to set that environment variable on the docker compose setup script.

Running takeout enable opensearch post update allows opensearch to properly run: http://localhost:9200/

[tcampbPPU]

https://www.postgresql.org/about/news/postgresql-174-168-1512-1417-and-1320-released-3018/

[mattstauffer]

Briliant, thanks!