Used Delayed error style for buck-check command

Summary:
confusionanddelay

The `pyre2 buck-check` command dumps its result into a JSON file for downstream to consume. What the command does on the console is pretty much invisible to most users given that the command gets invoked by Buck2 which always hide process stderr unless it fails. So dumping the error immediately is probably not that relevant for end users.

Reviewed By: samwgoldman

Differential Revision: D67177248

fbshipit-source-id: ac74f6cf349d8e0a82e1f9215ac63d1e7bf15265

pyre2/pyre2/bin/module/source_db.rs

@@ -155,9 +155,7 @@ impl BuckSourceDatabase {
 
     pub fn load(&self, name: ModuleName) -> (LoadResult, ErrorStyle) {
         match self.lookup(name) {
-            LookupResult::OwningSource(path) => {
-                (LoadResult::from_path(path), ErrorStyle::Immediate)
-            }
+            LookupResult::OwningSource(path) => (LoadResult::from_path(path), ErrorStyle::Delayed),
             LookupResult::ExternalSource(path) => (LoadResult::from_path(path), ErrorStyle::Never),
             LookupResult::NoSource => (
                 LoadResult::FailedToFind(anyhow!("Not a dependency or typeshed")),