Print current branch/database in REPL

[quinchs]

Fixes #1250

[aljazerzen]

This basically doubles the time between user hitting enter and CLI being ready for next command.

But there is no other way, so I guess ok.

[msullivan]

This basically doubles the time between user hitting enter and CLI being ready for next command.

But there is no other way, so I guess ok.

Can't we fetch it only once at connection time?

[quinchs]

Now only fetches at connection and if it's not cached

[aljazerzen]

Oh, yes - branch cannot be changed with EdgeQL queries, so it can be cached for the whole duration of a connection.

That said: we could just the the "branch" connection parameter and to make any requests to the database. I guess this would be more fragile since we both "database" param and "branch" param and some non-trivial logic deciding which branch we actually open the connection to.

Bottom line: current approach is good

[aljazerzen]

The interactive tests are failing because they expect to have "edgedb>" command prompt, but get "main>" instead.

[quinchs]

The interactive tests are failing because they expect to have "edgedb>" command prompt, but get "main>" instead.

I'll fix that