subscriber: fix missing event fields in Compact formatter

The line of code that prints the event's fields (including its message)
was accidentally deleted in 0a16972,
while backporting PR #1696 from `master` (where the `Compact`) formatter
implementation is significantly different.

This branch puts it back.

Fixes #1741

tracing-subscriber/src/fmt/format/mod.rs

@@ -906,15 +906,6 @@ where
             write!(writer, "{:0>2?} ", std::thread::current().id())?;
         }
 
-        if self.display_target {
-            write!(
-                writer,
-                "{}{}",
-                writer.bold().paint(meta.target()),
-                writer.dimmed().paint(":")
-            )?;
-        }
-
         let fmt_ctx = {
             #[cfg(feature = "ansi")]
             {
@@ -927,6 +918,17 @@ where
         };
         write!(writer, "{}", fmt_ctx)?;
 
+        if self.display_target {
+            write!(
+                writer,
+                "{}{}",
+                writer.bold().paint(meta.target()),
+                writer.dimmed().paint(":")
+            )?;
+        }
+
+        ctx.format_fields(writer.by_ref(), event)?;
+
         let dimmed = writer.dimmed();
         for span in ctx
             .event_scope()