[Fleet] Add version flag

[nchaulet]

Description

Add version flag to standalone command, pass version to cobra, that will handle the --version flag

Examples

[mergify[bot]]

This pull request does not have a backport label. Could you fix it @nchaulet? 🙏 To fixup this pull request, you need to add the backport labels for the needed branches, such as:

• backport-./d./d is the label to automatically backport to the 8./d branch. /d is the digit

[mergify[bot]]

backport-8.x has been added to help with the transition to the new branch 8.x. If you don't need it please use backport-skip label and remove the backport-8.x label.

[cmacknz]

make local
❯ ./bin/fleet-server --version
fleet-server version 9.0.0

It works!

[elastic-sonarqube[bot]]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube