Fix sticky header scroll bug

[Etheryte]

What does this PR change?

The legacy script that handles sticky headers doesn't account for the fact that some pages may have multiple sections which are sticky header candidates. In the future we want to move this over to a purely CSS solution since position: sticky is now widely supported, for the time being this PR fixes the infinite layout expansion bug.

GUI diff

No more infinite scroll.

• DONE

Documentation

• No documentation needed: bugfix

• DONE

Test coverage

ℹ️ If a major new functionality is added, it is strongly recommended that tests for the new functionality are added to the Cucumber test suite

• No tests: UI bug

• DONE

Links

https://suse.slack.com/archives/C02D130RBA6/p1726915321046259

• DONE

Changelogs

Make sure the changelogs entries you are adding are compliant with https://github.com/uyuni-project/uyuni/wiki/Contributing#changelogs and https://github.com/uyuni-project/uyuni/wiki/Contributing#uyuni-projectuyuni-repository

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• Re-run test "changelog_test"
• Re-run test "backend_unittests_pgsql"
• Re-run test "java_pgsql_tests"
• Re-run test "schema_migration_test_pgsql"
• Re-run test "susemanager_unittests"
• Re-run test "javascript_lint"
• Re-run test "spacecmd_unittests"

Before you merge

Check How to branch and merge properly!

[bisht-richa]

LGTM

[deneb-alpha]

LGTM