catch *any* exception

`listenLoop` was crashing when the client closed the connection during the handshake.  How this doesn't qualify as an `IOException` is beyond me.

ChangeLog.md

@@ -1,3 +1,5 @@
 # Changelog for gemcap
 
 ## Unreleased changes
+
+- fixed a bug that would cause the server to crash when the client aborted the handshake by rejecting the key

src/Network/Gemini/Capsule.hs

@@ -31,7 +31,7 @@ module Network.Gemini.Capsule (
 ) where
 
 import Control.Concurrent (forkIO)
-import Control.Exception (IOException, try)
+import Control.Exception (SomeException, try)
 import Control.Exception.Base (bracket, finally)
 import Control.Monad (void)
 import qualified Data.Connection as C
@@ -72,7 +72,7 @@ listenLoop sock params handler = do
   certRef <- newIORef Nothing
   let params' = adjustServerParams certRef params
   try (accept params' sock) >>= \case
-    Left (_::IOException) -> return ()
+    Left (_::SomeException) -> return ()
     Right conn            -> void $ forkIO $ finally
       (readIORef certRef >>= runConnection conn handler)
       (C.close conn)