Bump version for http-server pkg to fix audit

[leaysgur]

@miniflare/http-server package has deps to selfsigned package and it was reported as low severity vulnerabilities.

Logs by `npm i miniflare`

~/Codes
❯ mkdir miniflare-deps

~/Codes
❯ cd miniflare-deps

~/Codes/miniflare-deps
❯ npm init -y
Wrote to /Users/leader22/Codes/miniflare-deps/package.json:

{
  "name": "miniflare-deps",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "Yuji Sugiura",
  "license": "MIT"
}



~/Codes/miniflare-deps
❯ npm i miniflare

added 40 packages, and audited 41 packages in 2s

4 low severity vulnerabilities

To address all issues, run:
  npm audit fix

Run `npm audit` for details.

~/Codes/miniflare-deps
❯ npm audit
# npm audit report

node-forge  <1.0.0
Prototype Pollution in node-forge debug API. - https://github.com/advisories/GHSA-5rrq-pxf6-6jx5
fix available via `npm audit fix --force`
Will install [email protected], which is a breaking change
node_modules/node-forge
  selfsigned  1.1.1 - 1.10.14
  Depends on vulnerable versions of node-forge
  node_modules/selfsigned
    @miniflare/http-server  *
    Depends on vulnerable versions of selfsigned
    node_modules/@miniflare/http-server
      miniflare  >=2.0.0-next.1
      Depends on vulnerable versions of @miniflare/http-server
      node_modules/miniflare

4 low severity vulnerabilities

To address all issues (including breaking changes), run:
  npm audit fix --force

This PR updates selfsigned to 2.0.0 (major version up), but actual implementation seems not changed.
jfromaniello/selfsigned@v1.10.11...v2.0.0

[mrbbot]

Hey! 👋 Thanks for this PR! 😃 I've just released version 2.1.0 including this. You can find the full changelog here.

[leaysgur]

Thank you! 😆