Remove unnecessary Babel plugins

Object rest spread has been supported without these plugins for a long
time (since ~Node 5-8), and we are using the preset env plugin anyway,
so we can safely remove these plugins without any issue.

.babelrc

@@ -9,9 +9,5 @@
       }
     ],
     "@babel/preset-react"
-  ],
-  "plugins": [
-    "@babel/plugin-syntax-dynamic-import",
-    "@babel/plugin-proposal-object-rest-spread"
   ]
 }

package.json

@@ -82,8 +82,6 @@
     "@babel/cli": "^7.16.0",
     "@babel/core": "^7.16.5",
     "@babel/eslint-parser": "^7.16.5",
-    "@babel/plugin-proposal-object-rest-spread": "^7.16.5",
-    "@babel/plugin-syntax-dynamic-import": "^7.8.3",
     "@babel/preset-env": "^7.16.5",
     "adm-zip": "^0.4.13",
     "babel-jest": "^27.4.5",

yarn.lock

@@ -457,7 +457,7 @@
     "@babel/helper-plugin-utils" "^7.18.6"
     "@babel/plugin-syntax-numeric-separator" "^7.10.4"
 
-"@babel/plugin-proposal-object-rest-spread@^7.16.5", "@babel/plugin-proposal-object-rest-spread@^7.20.2":
+"@babel/plugin-proposal-object-rest-spread@^7.20.2":
   version "7.20.7"
   resolved "https://registry.yarnpkg.com/@babel/plugin-proposal-object-rest-spread/-/plugin-proposal-object-rest-spread-7.20.7.tgz#aa662940ef425779c75534a5c41e9d936edc390a"
   integrity sha512-d2S98yCiLxDVmBmE8UjGcfPvNEUbA1U5q5WxaWFUGRzJSVAZqm5W6MbPct0jxnegUZ0niLeNX+IOzEs7wYg9Dg==