Update dependencies from https://github.com/dotnet/source-build-externals build 20240820.1

Microsoft.SourceBuild.Intermediate.source-build-externals
 From Version 10.0.0-alpha.1.24419.1 -> To Version 9.0.0-alpha.1.24420.1

Author: dotnet-maestro[bot]

eng/Version.Details.xml

@@ -441,9 +441,9 @@
       <SourceBuild RepoName="command-line-api" ManagedOnly="true" />
     </Dependency>
     <!-- Intermediate is necessary for source build. -->
-    <Dependency Name="Microsoft.SourceBuild.Intermediate.source-build-externals" Version="10.0.0-alpha.1.24419.1">
+    <Dependency Name="Microsoft.SourceBuild.Intermediate.source-build-externals" Version="9.0.0-alpha.1.24420.1">
       <Uri>https://github.com/dotnet/source-build-externals</Uri>
-      <Sha>53509904f37cafa0771accdf404a5609c5ca9be5</Sha>
+      <Sha>ee22054b44ec9615dc3481c4decc1b007a83a2b0</Sha>
       <SourceBuild RepoName="source-build-externals" ManagedOnly="true" />
     </Dependency>
     <!-- Intermediate is necessary for source build. -->