### changes
#### remove trailing spaces
When I was using example I noticed trailing spaces.
So, this PR removes the trailing spaces of json file, README, and others.
`examples/with-jest-typescript/src/modules/cars/Overview.tsx` also has it, but this time it did not change as tslint error occurs at commit.
After discussion it was decided instead of rewriting `next/config` and `next/head` imports to `next-server/config` and `next-server/head` we should just allow importing them as `next/config` and `next/head`
Fixes: #6187
