Fix IO redirection for async execution in wxOSX

Don't try running non-bundled applications in wxCocoaLaunch(): this
prevents the code handling IO redirection from being used.

Check that we have a bundle, just like wxMacaunch(), used until
5b6af7002c, used to do.

Closes #18552.

See https://github.com/wxWidgets/wxWidgets/pull/1561

src/osx/cocoa/utils_base.mm

@@ -217,6 +217,14 @@ bool wxCocoaLaunch(const char* const* argv, pid_t &pid)
         return false ;
     }
 
+    // Don't try running non-bundled applications here, we don't support output
+    // redirection, which is important for them, unlike for the bundled apps,
+    // so let the generic Unix code handle them.
+    if ( [NSBundle bundleWithURL:url] == nil )
+    {
+        return false;
+    }
+
     // Loop through command line arguments to the bundle,
     // turn them into CFURLs and then put them in cfaFiles
     // For use to launch services call