Use babel.config.js instead of .babelrc

.babelrc

-{
-  "presets": [
-    "@babel/preset-env",
-    "@babel/preset-react"
-  ],
-  "plugins": [
-    "@babel/plugin-proposal-class-properties",
-  ]
-}

Dockerfile

@@ -17,7 +17,7 @@ COPY package*.json ./
 COPY webpack*.js ./
 
 # Babel 7 presets and plugins
-COPY .babelrc ./
+COPY babel.config.js ./
 
 # Bundle app source
 COPY src ./src

babel.config.js

+module.exports = function (api) {
+  api.cache(true);
+
+  const presets = [
+    '@babel/preset-env',
+    '@babel/preset-react'
+  ];
+  const plugins = [
+    '@babel/plugin-proposal-class-properties'
+  ];
+
+  return {
+    presets,
+    plugins
+  };
+};

package-lock.json

@@ -8165,7 +8165,8 @@
         "ansi-regex": {
           "version": "2.1.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "aproba": {
           "version": "1.2.0",
@@ -8580,7 +8581,8 @@
         "safe-buffer": {
           "version": "5.1.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "safer-buffer": {
           "version": "2.1.2",
@@ -8636,6 +8638,7 @@
           "version": "3.0.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "ansi-regex": "^2.0.0"
           }
@@ -8679,12 +8682,14 @@
         "wrappy": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "yallist": {
           "version": "3.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         }
       }
     },