chore: Tidy up the source generator in tests and samples (#4344)

Author: jamescrosswell

samples/Directory.Build.props

@@ -10,4 +10,11 @@
   <PropertyGroup Condition="'$(Configuration)' == 'Release' And $([MSBuild]::GetTargetPlatformIdentifier('$(TargetFramework)')) == 'ios'">
     <MtouchUseLlvm>false</MtouchUseLlvm>
   </PropertyGroup>
+
+  <ItemGroup>
+    <!-- So the source generators work for our samples... SDK users wouldn't need to do this  -->
+    <ProjectReference Include="$(MSBuildThisFileDirectory)..\src\Sentry.SourceGenerators\Sentry.SourceGenerators.csproj"
+                      OutputItemType="Analyzer"
+                      ReferenceOutputAssembly="false"/>
+  </ItemGroup>
 </Project>

samples/Sentry.Samples.Android/Sentry.Samples.Android.csproj

@@ -12,9 +12,6 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <ProjectReference Include="..\..\src\Sentry.SourceGenerators\Sentry.SourceGenerators.csproj"
-                      OutputItemType="Analyzer"
-                      ReferenceOutputAssembly="false"/>
     <ProjectReference Include="..\..\src\Sentry\Sentry.csproj" />
     <Using Include="Android.App.Activity" Alias="Activity" />
 

samples/Sentry.Samples.Ios/Sentry.Samples.Ios.csproj

@@ -44,9 +44,6 @@
   <ItemGroup>
     <!-- <PackageReference Include="Sentry" Version="..." /> -->
     <ProjectReference Include="..\..\src\Sentry\Sentry.csproj" />
-    <ProjectReference Include="..\..\src\Sentry.SourceGenerators\Sentry.SourceGenerators.csproj"
-                      OutputItemType="Analyzer"
-                      ReferenceOutputAssembly="false"/>
   </ItemGroup>
 
 </Project>

samples/Sentry.Samples.MacCatalyst/Sentry.Samples.MacCatalyst.csproj

@@ -44,9 +44,6 @@
   <ItemGroup>
     <!-- <PackageReference Include="Sentry" Version="..." /> -->
     <ProjectReference Include="..\..\src\Sentry\Sentry.csproj" />
-    <ProjectReference Include="..\..\src\Sentry.SourceGenerators\Sentry.SourceGenerators.csproj"
-                      OutputItemType="Analyzer"
-                      ReferenceOutputAssembly="false"/>
   </ItemGroup>
 
 </Project>

src/Sentry/CompilerServices/BuildProperties.cs

@@ -10,7 +10,7 @@ public static class BuildProperties
     /// <summary>
     /// The Build Variables generated from you csproj file and initialized by the Sentry Source Generated Module Initializer
     /// </summary>
-    public static IReadOnlyDictionary<string, string>? Values { get; private set; }
+    internal static IReadOnlyDictionary<string, string>? Values { get; set; }
 
     /// <summary>
     /// This is called by a Sentry Source-Generator module initializers to help us determine things like