typo fix and updates to test work section of readme

[xphyr]

What this PR does / why we need it:

This PR fixes a typo in the Readme, and also updates the section on running tests. The instructions say to run "test_links" and "test_spelling", however the make commands are "check_links" and "check_spelling". Commands were tested to ensure that they work.

Signed-off-by: Mark DeNeve markd@xphyr.net

[kubevirt-bot]

Hi @xphyr. Thanks for your PR.

I'm waiting for a kubevirt member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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[mazzystr]

Thank you for the updates!

/lgtm /approve

[kubevirt-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: mazzystr

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