runtimeModules are never in middleware layer, but maybe in middleware…

… chunks


> I would juest omit that and leave source maps on for them

Co-authored-by: Tobias Koppers <tobias.koppers@googlemail.com>

packages/next/build/webpack/plugins/middleware-source-maps-plugin.ts

@@ -41,9 +41,6 @@ class MiddlewareSourceMapsPlugin {
       compilation.hooks.buildModule.tap(PLUGIN_NAME, (module) => {
         module.useSourceMap = module.layer === 'middleware'
       })
-      compilation.hooks.runtimeModule.tap(PLUGIN_NAME, (module) => {
-        module.useSourceMap = module.layer === 'middleware'
-      })
     })
   }
 }