Use kubectl matching with cluster's version

[unexge]

Currently, we use stable version of kubectl (v1.32 as of today), and that might cause some problems as kubectl emits a warning:

WARNING: version difference between client (1.32) and server (1.29) exceeds the supported minor version skew of +/-1

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[unexge]

This PR also had this change originally:

Increase assume role duration to 75 minutes in end-to-end tests - Our assume role duration in our CI is 1 hour by default, but with the recent changes, our end-to-end test job started taking more than 1 hour sometimes, and that causes our CI to fail due to expired credentials.

But I'll move this change to a different PR as it requires some additional changes on the CI infra.

[jiaeenie]

Thanks for the fix @unexge, looks good to me!