Fix generating duplicates and omitting heading

[jihoon-seo]

What type of PR is this?

/kind bug

What this PR does / why we need it:

• (Remove duplicates in krel release-notes output #1993: "Remove duplicates in krel release-notes output")

Having headers in krel release-notes output caused the end result of k/k changelog to have duplicated headers. We had to fix this in 1.20 and again in 1.21 after the release.

• (Add missing 'Source Code' heading in krel output #2012: "Add missing 'Source Code' heading in krel output")

'Source Code' heading is missing in krel-generated files.
Please refer to https://github.com/kubernetes/kubernetes/pull/101299/files .

Which issue(s) this PR fixes:

• Fixes a part of Remove duplicates in krel release-notes output #1993 ("Remove duplicates in krel release-notes output")
• Fixes Add missing 'Source Code' heading in krel output #2012 ("Add missing 'Source Code' heading in krel output")

Special notes for your reviewer:

Does this PR introduce a user-facing change?

pkg/changelog: Add missing "Source Code" heading, fix upper-case consistency in headings, and remove duplicates

[jihoon-seo]

/hold

[jihoon-seo]

/unhold

[jihoon-seo]

CC: @wilsonehusin , PTAL!

[wilsonehusin]

this is awesome, thanks for contributing!

I think this warrants a release note? something like:

pkg/changelog: Add missing "downloads" heading and fix upper-case consistency in headings

otherwise, code is 👍🏼

/lgtm

[jihoon-seo]

@wilsonehusin Thank you for your suggestion.

I propose another suggestion which is almost the same:

pkg/changelog: Add missing "Source Code" heading, fix upper-case consistency in headings, and remove duplicates

Would it be okay to put this release note into the "Does this PR introduce a user-facing change?" field of this PR? 😊

[wilsonehusin]

ah good catch -- yes that looks better!

Would it be okay to put this release note into the "Does this PR introduce a user-facing change?" field of this PR? 😊

yep that's the right place to do it

[jihoon-seo]

@wilsonehusin Done putting. PTAL. Thank you! 😊

[wilsonehusin]

let's wait for people with approval powers, i don't think i have any here 😆

/priority backlog
/milestone v1.22

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jihoon-seo, saschagrunert

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