Upgrade agents from the app

[jesusgn90]

Tasks:

• [ ] Check if the agent is upgradeable
• [ ] Add button to upgrade it (API call)
• [ ] Give feedback about the upgrading process (pending API)

Pending API (https://github.com/wazuh/wazuh-api/issues/286)

[pablotr9]

Working on this branch https://github.com/wazuh/wazuh-splunk/tree/issue-488

• [x] Add button to upgrade it (API call)
• [x] Show upgrade button if agent is outdated
• [ ] * Give feedback about the upgrading process

[adri9valle]

• Changed: How check if agent is upgraded in the resolve.
• Added: Style to button. Give feedback about the upgrading process (pending API)