Fix shell terminating when an error occurs during completion

The shell asking for completion was exiting when PHP exited with a non-zero
status. This was due to `exit` being use instead of `return` in the context
of a BASH function.

This made it quite frustrating to develop the module, so I'm glad this is
now fixed.

Author: stecman

src/Stecman/Component/Symfony/Console/BashCompletion/CompletionHandler.php

@@ -394,7 +394,7 @@ function $funcName {
     STATUS=$?;
     if [ \$STATUS -ne 0 ]; then
         echo \$RESULT;
-        exit $?;
+        return \$?;
     fi;
 
     local cur;