Description of problem:
After upgrading a RHEL 7 system to RHEL8 the semanage port configuration is not fully preserved.
Customer has configured type `http_cache_port_t` to port 8000.
Leap fails to set this configuration because it conflicts with the existing configuration for port 8000 as type `soundd_port_t`.

Version-Release number of selected component (if applicable):
policycoreutils-python-utils-2.9-24.el8.noarch
leapp-0.15.1-1.el7_9.noarch

How reproducible:
always

Steps to Reproduce:
1. spin up a rhel7 image (I used kcli from the rhel7 image from the portal downloads)

~~~
# cat /etc/redhat-release 
Red Hat Enterprise Linux Server release 7.9 (Maipo)
~~~

2. check default SELinux port for http_cache and port 8000:

~~~
# semanage port -l |grep http_cache
http_cache_port_t              tcp      8080, 8118, 8123, 10001-10010
http_cache_port_t              udp      3130
# semanage port -l |grep 8000
soundd_port_t                  tcp      8000, 9433, 16001
~~~

3. Add/modify port 8000

~~~
# semanage port -a -t http_cache_port_t -p tcp 8000
ValueError: Port tcp/8000 already defined
# semanage port -l |grep http_cache
http_cache_port_t              tcp      8080, 8118, 8123, 10001-10010
http_cache_port_t              udp      3130
# semanage port -l |grep 8000
soundd_port_t                  tcp      8000, 9433, 16001
# semanage port -m -t http_cache_port_t -p tcp 8000
# semanage port -l |grep http_cache
http_cache_port_t              tcp      8000, 8080, 8118, 8123, 10001-10010
http_cache_port_t              udp      3130
# semanage port -l |grep 8000
http_cache_port_t              tcp      8000, 8080, 8118, 8123, 10001-10010
soundd_port_t                  tcp      8000, 9433, 16001
~~~

4. reboot and verify

~~~
# semanage port -l |grep http_cache
http_cache_port_t              tcp      8000, 8080, 8118, 8123, 10001-10010
http_cache_port_t              udp      3130
# semanage port -l |grep 8000
http_cache_port_t              tcp      8000, 8080, 8118, 8123, 10001-10010
soundd_port_t                  tcp      8000, 9433, 16001
~~~

5. perform the leapp upgrade

~~~
# subscription-manager repos --enable rhel-7-server-rpms
# subscription-manager repos --enable rhel-7-server-extras-rpms
# subscription-manager release --unset
# yum versionlock clear
# yum update
# reboot
# yum install leapp-upgrade
# leapp answer --section remove_pam_pkcs11_module_check.confirm=True
# rmmod floppy
# rmmod pata_acpi
# leapp upgrade --debug
# reboot
~~~

Actual results:
The selinux port config is not retained:

~~~
# semanage port -l |grep 8000
soundd_port_t                  tcp      8000, 9433, 16001
# semanage port -l |grep http_cache
http_cache_port_t              tcp      8080, 8118, 8123, 10001-10010
http_cache_port_t              udp      3130
~~~


Expected results:
SELinux configuration to be retained after Leapp upgrade

Additional info:
The log `/var/log/leapp/leapp-upgrade.log` shows that Leapp attempts to set the type but fails because a definition already exists for port 8000:
~~~
2023-08-10 10:26:53.522 INFO     PID: 1268 leapp.workflow.Applications.selinuxapplycustom: Importing the following SELinux customizations collected by "semanage export":
2023-08-10 10:26:55.156 WARNING  PID: 1268 leapp.workflow.Applications.selinuxapplycustom: Error applying "semanage port -a -t http_cache_port_t -r 's0' -p tcp 8000": ValueError: Port tcp/8000 already defined
~~~

This is identical to the error seen in step 3. above.

The resulting configuration may not be valid for SELinux and may need to be adressed in policycore-utils but Leapp needs to handle or at least warn about this issue.