Wrong display of volume minSize in shoot creation

[hebelsan]

What happened: We have created new volumeTypes in the gcp CloudProfile (hyperdisk-balanced, hyperdisk-extreme, hyperdisk-throughput):

- name: hyperdisk-balanced
    class: premium
    minSize: 4Gi
  - name: hyperdisk-extreme
    class: premium
    minSize: 64Gi
  - name: hyperdisk-throughput
    class: premium
    minSize: 2Ti

However the dashboard UI is not showing the correct minSize. We see 2 issues:

• Instead of showing the correct minSize of 4Gi or 64Gi it's always showing Minimum size is 20
• For hyperdisk-throughput with minSize 2Ti it's not showing any error at all

What you expected to happen: The UI shows the correct minSize if the input is too small

How to reproduce it (as minimally and precisely as possible): Create a gcp shoot with one of the three new volumeTypes hyperdisk-balanced, hyperdisk-extreme or hyperdisk-throughput

Anything else we need to know:

Environment: dev