fix use local beacon rest path error

[Linuxpizi]

Motivation

now, when i use local beacon rest service test to get records and transafer, first i create a client like

let client = Client::<N>::new("http://127.0.0.1:3030")?;

but the internal use Url::parse function will append / in suffix, it will be http://127.0.0.1:3030/.

when send a request to beacon rest service the url will become http://127.0.0.1:3030//testnet3/latest/height it is a invalid url

Test Plan

• [x] use origin public api test ok, all test done
• [x] use local snarkos beacon rest test done

Related PRs

(Link your related PRs here)

[Linuxpizi]

#1284