Check if build succeeds

Author: ArtyomVancyan

tox.ini

@@ -10,17 +10,20 @@ commands =
     npm install
     npm install -D @types/react@^16.0.0
     npm test
+    npm build
 
 [testenv:rc17]
 allowlist_externals = npm
 commands =
     npm install
     npm install -D @types/react@^17.0.0
     npm test
+    npm build
 
 [testenv:rc18]
 allowlist_externals = npm
 commands =
     npm install
     npm install -D @types/react@^18.0.0
     npm test
+    npm build