Remove redundant `SourceBuildTrimNetFrameworkTargets` property

[NikolaMilosavljevic]

We have originally added SourceBuildTrimNetFrameworkTargets property to most .NET repos to enable TFM trimming, in accordance with the original design: #3014

As a consequence, the following line was added to those repos (an example from installer):

https://github.com/dotnet/installer/blob/f8275a0edc0a90b593f2e3f73c4b9b3e908e3e22/eng/SourceBuild.props#LL8C50-L8C50

    <SourceBuildTrimNetFrameworkTargets>true</SourceBuildTrimNetFrameworkTargets>

After original implementation, TFM trimming work was further simplified, to use the opt-out logic, with: dotnet/arcade#13271

This property is not needed anymore, it causes unnecessary confusion and increased maintenance cost. Property should be removed at the earliest convenience.

To ensure proper tracking, for each repo, the list below should be updated with the PR link. Refer to original work (#3014) for the full list of repos and original changes. Note that some repos never used this property, i.e. emsdk and runtime.

Repositories

• Remove redundant SourceBuildTrimNetFrameworkTargets property arcade#13854
• Remove redundant SourceBuildTrimNetFrameworkTargets property aspnetcore#49022
• Remove redundant SourceBuildTrimNetFrameworkTargets property cecil#91
• Remove redundant SourceBuildTrimNetFrameworkTargets property command-line-api#2229
• Remove redundant SourceBuildTrimNetFrameworkTargets property deployment-tools#280
• Remove redundant SourceBuildTrimNetFrameworkTargets property diagnostics#4016
• Remove redundant SourceBuildTrimNetFrameworkTargets property format#1883
• Remove redundant SourceBuildTrimNetFrameworkTargets property fsharp#15487
• Remove redundant SourceBuildTrimNetFrameworkTargets property installer#16817
• Remove redundant SourceBuildTrimNetFrameworkTargets property msbuild#8952
• Remove redundant SourceBuildTrimNetFrameworkTargets property NuGet/NuGet.Client#5278
• Remove redundant SourceBuildTrimNetFrameworkTargets property razor#8866
• Remove redundant SourceBuildTrimNetFrameworkTargets property roslyn-analyzers#6713
• Remove redundant SourceBuildTrimNetFrameworkTargets property roslyn#68772
• Remove redundant SourceBuildTrimNetFrameworkTargets property sdk#33572
• Remove redundant SourceBuildTrimNetFrameworkTargets property sourcelink#1054
• Remove redundant SourceBuildTrimNetFrameworkTargets property symreader#292
• Remove redundant SourceBuildTrimNetFrameworkTargets property templating#6801
• Remove redundant SourceBuildTrimNetFrameworkTargets property test-templates#309
• Remove redundant SourceBuildTrimNetFrameworkTargets property microsoft/vstest#4577
• Remove redundant SourceBuildTrimNetFrameworkTargets property xdt#517
• Remove redundant SourceBuildTrimNetFrameworkTargets property xliff-tasks#798

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[MichaelSimons]

[Triage] @v-chayan, please work with @NikolaMilosavljevic to gain an understanding of the changes needed here.