Fix tftp image name in helm files

[nadvornik]

What does this PR change?

Correct name is proxy-tftpd. This is a leftover from #11421

Codespace

Check if you already have a running container clicking on

GUI diff

No difference.

• DONE

Documentation

• No documentation needed: add explanation. This can't be used if there is a GUI diff

• 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: add explanation

• DONE

Links

Related to #11421

• 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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• No changelog needed

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Re-run a test

If you need to re-run a test, please mark the related checkbox, it will be unchecked automatically once it has re-run:

• 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 "frontend_checks"
• Re-run test "spacecmd_unittests"

Before you merge

Check How to branch and merge properly!

[mbussolotto]

LGTM!

[mbussolotto]

not sure if you want to disable the changelog check, the rest is fine