Documentation: fix the broken links/dead links

[vipul-21]

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This the first PR to fix #10601. It addresses the broken link in the documentation as well as the links which can be ignored by the link checker.
The #10601 (comment) captures the items we need to close the issue.

Related: #10601

[qmonnet]

Looks great overall, thanks!

Please find some links to maybe adjust, and a few questions, inline below.

[qmonnet]

Not sure about this one, @pippolo84 could you please confirm this is the right link to use?

[pippolo84]

The correct link is this one: https://github.com/cilium/cilium/blob/main/daemon/k8s/resources.go

[qmonnet]

Does this skip checking the anchors? If so, why should we skip them, are they too hard to check?

[vipul-21]

As mentioned above I tried to make work on the anchors and changed the one that were
broken, but the md#anchor even though they exist are throwing the warnings. (not sure why ?)

/src/Documentation/gettingstarted/gettinghelp.rst:47: WARNING: broken link: https://github.com/cilium/cilium.io/blob/main/CONTRIBUTING.md#listing-cilium-training (Anchor 'listing-cilium-training' not found)
/src/Documentation/contributing/testing/e2e_legacy.rst:829: WARNING: broken link: https://github.com/cilium/cilium/blob/26dec4c4f4311df2b1a6c909b27ff7fe6e46929f/test/helpers/kubectl.go#L66-L67 (Anchor 'L66-L67' not found)
/src/Documentation/contributing/testing/e2e_legacy.rst:824: WARNING: broken link: https://github.com/cilium/cilium/blob/26dec4c4f4311df2b1a6c909b27ff7fe6e46929f/test/helpers/kubectl.go#L80-L102 (Anchor 'L80-L102' not found)
/src/Documentation/contributing/testing/e2e_legacy.rst:833: WARNING: broken link: https://github.com/cilium/cilium/blob/26dec4c4f4311df2b1a6c909b27ff7fe6e46929f/test/helpers/kubectl.go#L138-L147 (Anchor 'L138-L147' not found)
/src/Documentation/contributing/testing/ci.rst:40: WARNING: broken link: https://github.com/cilium/community/blob/main/CONTRIBUTOR-LADDER.md#organization-member (Anchor 'organization-member' not found)
/src/Documentation/observability/visibility.rst:78: WARNING: broken link: https://github.com/cilium/cilium/tree/master/api/v1/flow#flow-Layer7 (Anchor 'flow-Layer7' not found)
/src/Documentation/contributing/testing/bpf.rst:52: WARNING: broken link: https://github.com/cilium/ebpf/blob/49ebb13083886fc350167f2cde067e094a2b5037/elf_reader.go#L1074 (Anchor 'L1074' not found)
/src/Documentation/contributing/release/backports.rst:314: WARNING: broken link: https://github.com/cilium/release/blob/3c5fc2bdc38f8d290349a612a03cc83655f57a51/pkg/github/labels.go#L26 (Anchor 'L26' not found)
/src/Documentation/security/network/proxy/envoy.rst:17: WARNING: broken link: https://github.com/cilium/proxy#version-compatibility-matrix (Anchor 'version-compatibility-matrix' not found)
/src/Documentation/community/governance/commit_access.rst:210: WARNING: broken link: https://github.com/cncf/foundation/blob/main/README.md#other-content (Anchor 'other-content' not found)

/src/Documentation/network/servicemesh/grpc.rst:61: WARNING: broken link: https://github.com/fullstorydev/grpcurl#binaries (Anchor 'binaries' not found)
/src/Documentation/helm-reference.rst:740: WARNING: broken link: https://github.com/grafana/helm-charts/tree/main/charts/grafana#sidecar-for-dashboards (Anchor 'sidecar-for-dashboards' not found)
/src/Documentation/network/kubernetes/kata.rst:95: WARNING: broken link: https://github.com/kata-containers/packaging/tree/master/kata-deploy#run-a-sample-workload (Anchor 'run-a-sample-workload' not found)

[qmonnet]

I don't know :/. I'm travelling today but can take a look into it next week. Please ping me if I forget.

[qmonnet]

OK I had a look, I can reproduce but I don't understand either why these anchors are detected as broken. Maybe the link checker doesn't get exactly what we have in a browser.

So OK let's skip anchors for now, checking the rest of the links would already be a nice improvement.

[maintainer-s-little-helper]

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Please follow instructions provided in https://docs.cilium.io/en/stable/contributing/development/contributing_guide/#developer-s-certificate-of-origin

[qmonnet]

Looks good, thanks! Could you please:

• Squash the changes from your second commit into the first one
• Split into two commits, but differently: I would like all URL fixes in one, and the conf.py additions in a second. Ideally, the changes for conf.py should go along enabling the linkchecker in CI, in a separate PR, but I'm OK to have them here in a separate commit.
• Rebase on top of the current main branch, this should address the CI issues.

[maintainer-s-little-helper]

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Please follow instructions provided in https://docs.cilium.io/en/stable/contributing/development/contributing_guide/#developer-s-certificate-of-origin

[maintainer-s-little-helper]

Commit 10e04229a9e7d2d65b821345b9a8befb21611ea3 does not contain "Signed-off-by".

Please follow instructions provided in https://docs.cilium.io/en/stable/contributing/development/contributing_guide/#developer-s-certificate-of-origin

[qmonnet]

@vipul-21: You don't have to rebase the branch every time it gets out-of-date (you only need to do this if there are merge conflicts).

OK, I think this PR is ready. It touches documentation only, all base tests including for docs are green. We don't have a review for sig-k8s but we're not changing the contents of the docs, just fixing the links; and the new links all look good to me.

Let's get this merged to fix the docs, and to unblock #27116.