Split dist file creation and version replacing from main build script

scripts/replace-version.js

@@ -0,0 +1,20 @@
+const fs = require('fs-extra');
+
+function replaceVersionPlaceholder(version) {
+  const staticJsFilesPath = './build/static/js';
+  const versionPlaceholder = '%_VERSION_%';
+
+  const isMainFile = (file) => file.startsWith('main.') && file.endsWith('.js');
+  const [ mainJsFile ] = fs.readdirSync(staticJsFilesPath).filter(isMainFile);
+  const filePath = `${staticJsFilesPath}/${mainJsFile}`;
+  const fileContent = fs.readFileSync(filePath, 'utf-8');
+  const replaced = fileContent.replace(versionPlaceholder, version);
+
+  fs.writeFileSync(filePath, replaced, 'utf-8');
+}
+
+const version = process.env.VERSION;
+
+if (version) {
+  replaceVersionPlaceholder(version);
+}