SRE-777 add helm chart for N9 Agent

[RemiLis]

No description provided.

[ian-bartholomew]

Added a codefresh config and codeowners files. There are a couple of quick linting fixes

[triluch]

Some cosmetics and kube-linter issues left. After adding fixes for linter, make sure you test if the agent works with some queries defined for its datasource (for example it may fail if it tries to put some temporary files somewhere we don't expect).
For default limits I would suggest something along the lines of 1core and 1Gi mem (it depends on number of queries defined for DS, so it's not like one size suits all).
Other that what kube-linter found I would also add allowPrivilegeEscalation: false in security context.

[RemiLis]

@triluch Thanks Andrzej I have added all tips from kube-linter and also allowPrivilegeEscalation one

[triluch]

Looks good, just make sure agents works okay with those security changes and we can go ;)