[release/5.0] [browser][crypto] Remove restraining not supported attribute Primitives (#43441)

Co-authored-by: Kenneth Pouncey <kjpou@pt.lu>

src/libraries/System.Security.Cryptography.Primitives/Directory.Build.props

@@ -2,7 +2,5 @@
   <Import Project="..\Directory.Build.props" />
   <PropertyGroup>
     <StrongNameKeyId>Microsoft</StrongNameKeyId>
-    <IncludePlatformAttributes>true</IncludePlatformAttributes>
-    <UnsupportedOSPlatforms>browser</UnsupportedOSPlatforms>
   </PropertyGroup>
-</Project>
+</Project>