Webpack bug

The bug will crash webpack watching mode with error TypeError: Cannot read property 'jsonData' of undefined

Steps to reproduce

1. Clone this repo
2. Install dependencies npm ci
3. Run webpack watch mode npm start
4. Make some changes to ./src/index.js and save it to trigger rebuild
5. After second save webpack will crash with following error:

   TypeError: Cannot read property 'jsonData' of undefined
       at JsonGenerator.getSize (/workspaces/js-ts/webpack5-json-data-bug/node_modules/webpack/lib/json/JsonGenerator.js:119:31)
       at NormalModule.size (/workspaces/js-ts/webpack5-json-data-bug/node_modules/webpack/lib/NormalModule.js:1224:43)
       at NormalModule.cleanupForCache (/workspaces/js-ts/webpack5-json-data-bug/node_modules/webpack/lib/NormalModule.js:364:9)
       at NormalModuleFactory.cleanupForCache (/workspaces/js-ts/webpack5-json-data-bug/node_modules/webpack/lib/NormalModuleFactory.js:670:11)
       at Compiler._cleanupLastNormalModuleFactory (/workspaces/js-ts/webpack5-json-data-bug/node_modules/webpack/lib/Compiler.js:383:34)
       at Compiler.createNormalModuleFactory (/workspaces/js-ts/webpack5-json-data-bug/node_modules/webpack/lib/Compiler.js:1049:8)
       at Compiler.newCompilationParams (/workspaces/js-ts/webpack5-json-data-bug/node_modules/webpack/lib/Compiler.js:1071:30)
       at Compiler.compile (/workspaces/js-ts/webpack5-json-data-bug/node_modules/webpack/lib/Compiler.js:1082:23)
       at /workspaces/js-ts/webpack5-json-data-bug/node_modules/webpack/lib/Watching.js:188:19
       at Hook.eval [as callAsync] (eval at create (/workspaces/js-ts/webpack5-json-data-bug/node_modules/tapable/lib/HookCodeFactory.js:33:10), <anonymous>:15:1)