Imported Upstream version 6.8.0.73

Former-commit-id: d18deab1b47cfd3ad8cba82b3f37d00eec2170af

external/linker/eng/common/post-build/darc-gather-drop.ps1

@@ -19,7 +19,17 @@ try {
     ExitWithExitCode $exitCode
   }
 
+  # For now, only use a dry run.
+  # Ideally we would change darc to enable a quick request that
+  # would check whether the file exists that you can download it,
+  # and that it won't conflict with other files.
+  # https://github.com/dotnet/arcade/issues/3674
+  # Right now we can't remove continue-on-error because we ocassionally will have
+  # dependencies that have no associated builds (e.g. an old dependency).
+  # We need to add an option to baseline specific dependencies away, or add them manually
+  # to the BAR.
   darc gather-drop --non-shipping `
+    --dry-run `
     --continue-on-error `
     --id $BarBuildId `
     --output-dir $DropLocation `