Update dependencies from https://github.com/dotnet/roslyn build 20200819.4 (#25193)

[master] Update dependencies from dotnet/roslyn
- Updates:
  - Microsoft.Net.Compilers.Toolset: from 3.8.0-2.20414.4 to 3.8.0-2.20419.4

Author: dotnet-maestro[bot]

eng/Version.Details.xml

@@ -317,9 +317,9 @@
       <Uri>https://github.com/dotnet/arcade</Uri>
       <Sha>56a95cc477558c1ccdf16d7abe962849ea970ba4</Sha>
     </Dependency>
-    <Dependency Name="Microsoft.Net.Compilers.Toolset" Version="3.8.0-2.20414.4">
+    <Dependency Name="Microsoft.Net.Compilers.Toolset" Version="3.8.0-2.20419.4">
       <Uri>https://github.com/dotnet/roslyn</Uri>
-      <Sha>beada51586dedc46a7fe5ca381ffb10e2b177070</Sha>
+      <Sha>afb288f6c778c18003e89d8dd8ca94106df18702</Sha>
     </Dependency>
   </ToolsetDependencies>
 </Dependencies>

eng/Versions.props

@@ -62,7 +62,7 @@
   -->
   <PropertyGroup Label="Automated">
     <!-- Packages from dotnet/roslyn -->
-    <MicrosoftNetCompilersToolsetPackageVersion>3.8.0-2.20414.4</MicrosoftNetCompilersToolsetPackageVersion>
+    <MicrosoftNetCompilersToolsetPackageVersion>3.8.0-2.20419.4</MicrosoftNetCompilersToolsetPackageVersion>
     <!-- Packages from dotnet/runtime -->
     <MicrosoftExtensionsDependencyModelPackageVersion>5.0.0-rc.1.20417.14</MicrosoftExtensionsDependencyModelPackageVersion>
     <MicrosoftNETCoreAppInternalPackageVersion>5.0.0-rc.1.20417.14</MicrosoftNETCoreAppInternalPackageVersion>