Default to in-cluster config and remove kube config requirements

[chrisdoherty4]

The Kubernetes configuration currently required via the CLI isn't strictly required. If we aren't in-cluster and nothing was supplied it will naturally fail on loading. This change removes the checks entirely and lets the client creation process error out naturally.

[codecov]

Codecov Report

Merging #105 (c67879c) into main (27db950) will decrease coverage by 2.51%.
The diff coverage is 0.00%.

❗ Current head c67879c differs from pull request most recent head dc9a812. Consider uploading reports for the commit dc9a812 to get more accurate results

@@            Coverage Diff             @@
##             main     #105      +/-   ##
==========================================
- Coverage   42.68%   40.17%   -2.52%     
==========================================
  Files           8        8              
  Lines         581      575       -6     
==========================================
- Hits          248      231      -17     
- Misses        302      311       +9     
- Partials       31       33       +2     

Impacted Files	Coverage Δ
hardware/client.go	0.00% <ø> (ø)
hardware/kubernetes.go	47.52% <0.00%> (+1.37%)	⬆️
grpc/server.go	43.67% <0.00%> (-10.76%)	⬇️

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[micahhausler]

LGTM