Safer cobbler get_profile cast

[cbosdo]

What does this PR change?

Getting the list of cobbler profiles happens in two steps:

• calling cobbler's get_profiles API to list all the profiles
• calling cobbler's get_profile API to get more info on each profile

In between those two calls, some of the profiles could be gone due to concurrent deletion. In such a case get_profile will return "~" which means null.

Filter out the "~" returns to avoid the class cast exception and better reflect reality.

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

• No tests: already covered

• Unit tests were added

• Cucumber tests were added

• [ ] DONE

Links

Issue(s): https://github.com/SUSE/spacewalk/issues/24846 Port(s): https://github.com/SUSE/spacewalk/pull/24916

• [X] 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

If you don't need a changelog check, please mark this checkbox:

• [ ] No changelog needed

If you uncheck the checkbox after the PR is created, you will need to re-run changelog_test (see below)

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 "javascript_lint"
• [ ] Re-run test "spacecmd_unittests"

Before you merge

Check How to branch and merge properly!