Remove sizereport step

Apparently it doesn't exist anymore, even though it was referenced in Travis.

.github/workflows/node.js.yml

@@ -1,6 +1,3 @@
-# This workflow will do a clean install of node dependencies, build the source code and run tests across different versions of node
-# For more information see: https://help.github.com/actions/language-and-framework-guides/using-nodejs-with-github-actions
-
 name: Node.js CI
 
 on: [push, pull_request]
@@ -23,4 +20,3 @@ jobs:
         node-version: '${{ steps.nvmrc.outputs.node_version }}'
     - run: npm ci
     - run: npm run build
-    - run: npm run sizereport