kops 1.31 not reading cluster server API endpoint from local "~/.kube/config"

/kind bug

**1. What `kops` version are you running? The command `kops version`, will display
this information.**
`Client version: 1.31.0 (git-v1.31.0)`

**2. What Kubernetes version are you running? `kubectl version` will print the
version if a cluster is running or provide the Kubernetes version specified as
a `kops` flag.**
n/a

**3. What cloud provider are you using?**
AWS

**4. What commands did you run? What is the simplest way to reproduce this issue?**
`kops rolling-update cluster`
or
`kops reconcile cluster --yes`

**5. What happened after the commands executed?**
```
Using cluster from kubectl context: dev.private-dns.com

Unable to reach the kubernetes API.
Use --cloudonly to do a rolling-update without confirming progress with the k8s API

Error: error listing nodes in cluster: Get "https://api.dev.private-dns.com/api/v1/nodes": dial tcp: lookup api.dev.private-dns.com on 127.0.0.53:53: no such host
```

**6. What did you expect to happen?**
The kubernetes cluster server API endpoint used by kops to be the one configured in the local `~/.kube/config` file (under `.clusters[]|select(.name=="").cluster.server`) instead of the "default" value inferred by the `cluster_name` (e.g. `https://api.dev.public-dns.com:8443` vs ~`https://api.dev.private-dns.com`~).

**7. Please provide your cluster manifest. Execute
`kops get --name my.example.com -o yaml` to display your cluster manifest.
You may want to remove your cluster name and other sensitive information.**

```yaml
n/a
```

**8. Please run the commands with most verbose logging by adding the `-v 10` flag.
Paste the logs into this report, or in a gist and provide the gist link here.**
```
$ kops rolling-update cluster
I0210 11:33:55.071763 2246 loader.go:395] Config loaded from file: /home/user/.kube/config
Using cluster from kubectl context: dev.private-dns.com

I0210 11:33:55.072646 2246 factory.go:98] state store s3://some-s3-bucket
I0210 11:33:55.073014 2246 s3context.go:350] unable to read /sys/devices/virtual/dmi/id/product_uuid, assuming not running on EC2: open /sys/devices/virtual/dmi/id/product_uuid: permission denied
I0210 11:33:55.073252 2246 s3context.go:192] defaulting region to "us-east-1"
I0210 11:33:55.423361 2246 s3context.go:228] found bucket in region "us-west-2"
I0210 11:33:55.424839 2246 s3fs.go:405] Reading file "s3://some-s3-bucket/dev.private-dns.com/config"
I0210 11:33:56.045827 2246 clientset.go:114] Using keystore path: "s3://some-s3-bucket/dev.private-dns.com/pki"
I0210 11:33:56.046624 2246 aws_utils.go:52] Querying EC2 for all valid regions
I0210 11:33:56.478535 2246 aws_cloud.go:2023] Querying EC2 for all valid zones in region "us-west-2"
I0210 11:33:57.192625 2246 s3fs.go:405] Reading file "s3://some-s3-bucket/dev.private-dns.com/pki/private/kubernetes-ca/keyset.yaml"
I0210 11:33:57.379893 2246 certificate.go:104] Parsing pem block: "CERTIFICATE"
I0210 11:33:57.380479 2246 privatekey.go:194] Parsing pem block: "RSA PRIVATE KEY"
I0210 11:33:58.065080 2246 envvar.go:172] "Feature gate default state" feature="WatchListClient" enabled=false
I0210 11:33:58.065453 2246 envvar.go:172] "Feature gate default state" feature="InformerResourceVersion" enabled=false
I0210 11:33:58.065894 2246 round_trippers.go:466] curl -v -XGET -H "Accept: application/json, */*" -H "User-Agent: kops" 'https://api.dev.private-dns.com/api/v1/nodes'
I0210 11:33:58.085164 2246 round_trippers.go:495] HTTP Trace: DNS Lookup for api.dev.private-dns.com resolved to []
I0210 11:33:58.085590 2246 round_trippers.go:553] GET https://api.dev.private-dns.com/api/v1/nodes in 19 milliseconds
I0210 11:33:58.085702 2246 round_trippers.go:570] HTTP Statistics: DNSLookup 18 ms Dial 0 ms TLSHandshake 0 ms Duration 19 ms
I0210 11:33:58.085796 2246 round_trippers.go:577] Response Headers:
Unable to reach the kubernetes API.
Use --cloudonly to do a rolling-update without confirming progress with the k8s API

Error: error listing nodes in cluster: Get "https://api.dev.private-dns.com/api/v1/nodes": dial tcp: lookup api.dev.private-dns.com on 127.0.0.53:53: no such host
```

**9. Anything else do we need to know?**
This undesired behavior is only happening since kops 1.31 during the `rolling-update` phase (either via `kops rolling-update cluster` or `kops reconcile cluster --yes`). All earlier kops versions (including `kops 1.30.4`) are working as expected.