create getPendingConfigurationChangeRequest for agents to poll

[swaroopar]

• [ ] create new API getPendingConfigurationChangeRequest /xpanse/agent/poll/{serviceId}/{resourceName}
• [ ] No authentication.
• [ ] Mandatory query params – ServiceId and ResourceName
• [ ] Return the oldest request with status PENDING.
• [ ] If any polling request is in IN-PROGRESS for the specific serviceId and resourceName, then reject new request – ConfigUpdateInProgressAlreadyException
• [ ] Return – OrderId, config parameters as a map, ansibleScriptConfig (from OCL) and ansible inventory. - Define a data model for this.
• [ ] Build ansible Inventory as JSON with only group name, host name and IP.
• [ ] This API Controller must be activated only when a specific profile is provided. Profile name - 'agent-api'

Depends on https://github.com/eclipse-xpanse/xpanse/issues/1868

sample ansible inventory in JSON format

{
    "zookeeper": {
        "hosts": {
            "zookeeper-dfdfd": {
                "ansible_host": "192.168.11.2"
            },
        },
    },
    "kafka-broker": {
        "hosts": {
            "kafka-borker-dfdfdfd": {
                "ansible_host": "192.168.11.3"
            },
            "kafka-borker-absdf": {
                "ansible_host": "192.168.11.4"
            },
        },
    }
}