Fix broken link in docs

[fiunchinho]

What type of PR is this?

/kind bug
/kind documentation

What this PR does / why we need it:
There is a broken link in the docs.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

Special notes for your reviewer:
The root cause is CAPI renaming clusterctl config cluster to clusterctl generate cluster.

TODOs:

• squashed commits
• includes documentation
• adds unit tests

Release note:

Fix broken link in docs after clusterctl changes

[k8s-ci-robot]

Hi @fiunchinho. Thanks for your PR.

I'm waiting for a kubernetes-sigs 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.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[CecileRobertMichon]

/ok-to-test

[alexeldeib]

well, our link check works 😃

[nader-ziada]

@fiunchinho can you please add a release note, the PR looks good otherwise

[fiunchinho]

Done

[nader-ziada]

the links check in the markdown-link-check all passed

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: nader-ziada

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