Azure Linux Diagnostic Extension: Does not install on RHEL 8.1 due to lack of policycoreutils-python package

I appreciate it's not supported yet, but even after installing python2 and setting python alternative on RHEL 8.1 the extension still won't install.

It appears it keeps attempting to install the policycoreutils-python package which has now been replaced by policycoreutils-python-utils

```
2020/08/05` 19:01:35 [Microsoft.Azure.Diagnostics.LinuxDiagnostic-3.0.129] Enable,error,1,Failed to set up mdsd dependencies: package policycoreutils-python is not installed
2020/08/05 19:01:35 Last metadata expiration check: 0:27:44 ago on Wed 05 Aug 2020 06:32:49 PM UTC.
2020/08/05 19:01:35 No match for argument: policycoreutils-python
2020/08/05 19:01:35 Error: Unable to find a match: policycoreutils-python
2020/08/05 19:01:35 tar-1.30-4.el8.x86_64
2020/08/05 19:01:35
2020/08/05 19:01:35 [Microsoft.Azure.Diagnostics.LinuxDiagnostic-3.0.129] Enable,error,-1,Enabled failed
```

Start by tracing the Azure Linux Diagnostic Extension dependency setup that reports the missing policycoreutils-python package, using the RHEL 8.1 log in the issue as the reproduction. Verify the replacement policycoreutils-python-utils package is handled and confirm the extension installs successfully on RHEL 8.1.

Written by the indexing model from the issue text.