update last sync refresh timestamp only when products were synced

[mcalmer]

What does this PR change?

update last sync refresh timestamp only when at least one time products were synced before.
This happens when PAYG Update Task only refreshing repositories, but never products were synchronized

GUI diff

No difference.

• DONE

Documentation

• No documentation needed: only internal and user invisible changes

• DONE

Test coverage

• Unit tests were updated

• DONE

Links

Port(s): https://github.com/SUSE/spacewalk/pull/24717

• 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 "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"

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[github-actions]

👋 Hello! Thanks for contributing to our project.
Acceptance tests will take some time (aprox. 1h), please be patient ☕
You can see the progress at the end of this page and at https://github.com/uyuni-project/uyuni/pull/8968/checks
Once tests finish, if they fail, you can check 👀 the cucumber report. See the link at the output of the action.
You can also check the artifacts section, which contains the logs at https://github.com/uyuni-project/uyuni/pull/8968/checks.

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Reference tests:

• https://github.com/uyuni-project/uyuni/actions/workflows/acceptance_tests_secondary_parallel.yml?query=event%3Aschedule

• https://github.com/uyuni-project/uyuni/actions/workflows/acceptance_tests_secondary.yml?query=event%3Aschedule

KNOWN ISSUES

Sometimes the build can fail when pulling new jar files from download.opensuse.org . This is a known limitation. Given this happens rarely, when it does, all you need to do is rerun the test. Sorry for the inconvenience.

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Happy hacking!
⚠️ You should not merge if acceptance tests fail to pass. ⚠️

[github-actions]

Suggested tests to cover this Pull Request

• srv_sync_channels
• srv_disable_local_repos_off
• srv_menu
• srv_first_settings
• srv_task_status_engine
• srv_sync_products
• srv_enable_sync_products
• sle_ssh_minion
• min_salt_migration
• min_salt_install_with_staging
• srv_create_repository
• proxy_register_as_minion_with_script
• min_deblike_salt
• allcli_overview_systems_details
• min_salt_formulas
• min_project_lotus
• srv_docker_cve_audit
• minssh_move_from_and_to_proxy
• min_salt_install_package
• srv_datepicker
• min_salt_openscap_audit
• minkvm_guests
• min_monitoring
• min_recurring_action
• min_salt_minion_details
• min_rhlike_openscap_audit
• srv_distro_cobbler
• srv_menu_filter
• srv_custom_system_info
• min_salt_minions_page
• min_deblike_salt_install_package
• min_empty_system_profiles
• min_cve_id_new_syntax
• min_ssh_tunnel
• min_move_from_and_to_proxy
• srv_delete_channel_with_tool
• min_ansible_control_node
• srv_power_management_redfish
• min_bootstrap_script
• allcli_update_activationkeys
• min_rhlike_monitoring
• srv_channel_api
• allcli_software_channels_dependencies
• srv_content_lifecycle
• srv_add_rocky8_repositories
• min_cve_audit
• min_salt_mgrcompat_state
• min_config_state_channel
• srv_reportdb
• srv_delete_channel_from_ui
• buildhost_bootstrap
• minssh_salt_install_package
• allcli_reboot
• minssh_bootstrap_api
• proxy_retail_pxeboot_and_mass_import
• min_rhlike_salt_install_package_and_patch
• min_deblike_monitoring
• srv_wait_for_reposync
• min_deblike_salt_install_with_staging
• min_check_patches_install
• srv_user_configuration_salt_states
• srv_scc_user_credentials
• srv_cobbler_distro
• min_rhlike_salt
• min_salt_lock_packages
• proxy_branch_network
• min_bootstrap_api
• minssh_ansible_control_node
• srv_channels_add
• allcli_action_chain
• min_salt_formulas_advanced
• srv_power_management
• srv_clone_channel_npn
• srv_create_activationkey
• min_salt_user_states
• allcli_config_channel
• min_virthost
• min_deblike_openscap_audit
• min_action_chain
• min_config_state_channel_subscriptions
• buildhost_docker_auth_registry
• srv_handle_software_channels_with_ISS_v2
• min_timezone
• buildhost_osimage_build_image
• srv_manage_activationkey
• srv_advanced_search
• min_activationkey
• allcli_software_channels
• min_bootstrap_reactivation
• srv_maintenance_windows
• min_salt_pkgset_beacon
• proxy_as_pod_basic_tests
• buildhost_docker_build_image
• sle_minion
• min_deblike_ssh
• min_salt_software_states
• min_rhlike_ssh
• minssh_action_chain
• min_custom_pkg_download_endpoint
• allcli_system_group
• srv_manage_channels_page
• min_bootstrap_ssh_key
• min_retracted_patches
• min_change_software_channel