feat: support timeout in rpc

[zhangyouxin]

Description

Currently there is no timeout for the lumos rpc methods:

import { RPC } from '@ckb-lumos/rpc'
const rpc = new RPC('YOUR RPC URL')
// if there is something wrong with network or rpc server causing it stuck
// the rpc requests will never return 
await rpc.getBlock("0x1")

This pr fixes this by adding a defaut timeout(30 seconds) to the rpc methods and provides a parameter on RPC constructor which user can customize timeout configuration:

import { RPC } from '@ckb-lumos/rpc'
const rpc = new RPC('YOUR RPC URL', { timeout: 1 }) // milliseconds

// throws time exceeded error
await rpc.getBlock("0x1")

Type of change

• Refactor (non-breaking change)

How Has This Been Tested?

• An example is provided to test this feature.
• Added test cases

[vercel]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

Name	Status	Preview	Updated
lumos-website	✅ Ready (Inspect)	Visit Preview	Sep 28, 2022 at 3:32AM (UTC)

[codecov]

Codecov Report

Merging #432 (f7a472b) into develop (064c601) will increase coverage by 0.00%.
The diff coverage is 95.23%.

@@           Coverage Diff            @@
##           develop     #432   +/-   ##
========================================
  Coverage    82.28%   82.28%           
========================================
  Files           95       95           
  Lines        19701    19717   +16     
  Branches      1863     1861    -2     
========================================
+ Hits         16210    16225   +15     
- Misses        3437     3438    +1     
  Partials        54       54           

Impacted Files	Coverage Δ
packages/rpc/src/index.ts	72.67% <90.90%> (+0.55%)	⬆️
packages/rpc/src/method.ts	97.59% <100.00%> (+0.29%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 064c601...f7a472b. Read the comment docs.

[homura]

LGTM