Fix build:backends-activated command

build:backends-activated can now run the ```npm run build:backends``` command when running ```npm run build:backends-activated```

{{cookiecutter.project_shortname}}/package.json

@@ -19,7 +19,7 @@
     "prepublishOnly": "npm run validate-init",
     "build:js": "webpack --mode production",
     "build:backends": "dash-generate-components ./src/lib/components {{ cookiecutter.project_shortname }} -p package-info.json --r-prefix '{{ cookiecutter.r_prefix }}' --jl-prefix '{{ cookiecutter.jl_prefix }}' --ignore \\.test\\.",
-    "build:backends-activated": "(. venv/bin/activate || venv\\scripts\\activate && npm run build:py_and_r)",
+    "build:backends-activated": "(. venv/bin/activate || venv\\scripts\\activate && npm run build:backends)",
     "build": "npm run build:js && npm run build:backends",
     "build:activated": "npm run build:js && npm run build:backends-activated"
   },