Add message when no contexts are found in kubeconfig

[ChaturvediSulabh]

See the proposal here

What did I do?

1. Added message for empty contexts in both fzf.go and lists.go
2. Updated Implementation test 17
3. Tested Locally

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[ahmetb]

You need to implement integration tests as well I believe.

[googlebot]

CLAs look good, thanks!

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[ChaturvediSulabh]

@googlebot I fixed it

@googlebot I fixed it

[ChaturvediSulabh]

You need to implement integration tests as well I believe.

test case 17, delete several contexts validates this, I've updated the test case. Should I still write a separate test for this?

[ahmetb]

you're right it's technically capturing this case, but it's more ideal if we copy-paste it into its own test case. technically we want to have 1:1 mapping between "behavior we want to test" and "integration test case".