Fix fatal LoadException

[cschramm]

It looks like this rarely ever manifests, but we erroneously stopped catching the exception in c71294c.

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

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[infirit]

It's not a common error but as it's fatal, should we also include it in 2.4.4?

[cschramm]

Makes sense, yes.

I think this did not bite us yet because it is not reachable with affected versions of blueman alone. You either have to modify /org/blueman/general/plugin-list, e.g. to ['DhcpClient'], or adopt such a value from blueman 2.0 which seems to be the case in Debian #1082668. Enabling a plugin in the plugin manager will automatically disable all conflicting ones, so that e.g. DhcpClient will not be set without !NMPANSupport.