Some feature names used in tests had minor differences compared to
the well-known ones from `curl -V`. This patch syncs them to make test
results easier to grok.
Closes#14183
- add websockets support to sws
- 2300: first very basic websockets test
- 2301: first libcurl test for ws (not working yet)
- 2302: use the ws callback
- 2303: test refused upgrade