Adding CE2 information to js fetch backends doc
Adding CE2 information to js fetch backends doc

I had a bit of trouble identifying what the artifact name would be for CE2, so I figured this might help others in the future so they don't need to browse `https://repo1.maven.org/maven2/com/softwaremill/sttp/client3/` to find the dependency
softwaremill/sttp,softwaremill/sttp,softwaremill/sttp