fix: Set defaults for the securityContext

[maksym-iv-ef]

Description

Introduce default security context for the deployment to align with trivy rules:

securityContext:
  capabilities:
    drop:
    - ALL
  readOnlyRootFilesystem: true
  runAsNonRoot: true
  runAsUser: 1000
  allowPrivilegeEscalation: false
  seccompProfile:
    type: RuntimeDefault

Please take the rules into the account when upgrading

[kgrubb]

this looks good to me. i originally was going to say to make this a major version bump since its a breaking change technically, but i think the only situation where its breaking is if readOnlyRootFilesystem is turned on (the change in this pr) and the collector writes state/logs to an unmounted path, which it doesn't do by default anyway.

[maksym-iv-ef]

this looks good to me. i originally was going to say to make this a major version bump since its a breaking change technically, but i think the only situation where its breaking is if readOnlyRootFilesystem is turned on (the change in this pr) and the collector writes state/logs to an unmounted path, which it doesn't do by default anyway.

Moreover, we are on the v0.x.x, where minor version bumps can have breaking changes