Update chart version to "0.2.1"

[Neumann-Nils]

Description

As the last PR #241 changed some parts of the installation (mainly the naming from networkPolicy to networkPolicies), we should have updated the version in the Chart.yaml.

I bumped the version from 0.2.0 to 0.2.1.

Checklist

Before submitting this PR, please make sure:

• [x] your code builds clean with make
• [x] your code lets succeed unit tests with make test
• [x] your code lets succeed integration tests
• [x] you have documented new or changed features