BuildCheck API: Add support for project configurations in results reporting

### Context

In https://github.com/dotnet/msbuild/pull/10237 we added `ProjectConfigurationId` into the OM - so that Check authors can themselves partition incoming events and produced reports by configurations (E.g. in case of a build of multitargeted project - that will in fact have multiple distinct executions).

There is however no support for using the provided Id in the diagnostic results reporting (`BuildCheckDataContext.ReportResult`) - that would then lead to more user friendly reporting - e.g. the abbility to autofill configuration into the reports (e.g. 'proj.csproj (net9.0,Relase,AnyCPU) (12, 5) Some problem description') or groupping of findings (e.g. 'proj.csproj (12, 5) Some problem description (hit in configurations: net472; net9.0)')

### Goals
* `ProjectConfigurationId` can be specified in reporting API (`BuildCheckDataContext.ReportResult`)
* Infrastructure keeps id->string description mapping and is able to attach the friendly description of configuration to result if Id was attached
* (optional) - infrastructure is able to deduplicate same findings for different configurations, if deduplication was explicitly requested by results reporting api (flag would need to be added; caching of results would need to be added)