fix(UserPrefRepo): update personal access token format

[mt-yohei-koyama]

Summary

GitHub changed the format of personal access token and this makes token validation failure.
https://github.blog/2021-04-05-behind-githubs-new-authentication-token-formats/

This PR is for supporting the new GitHub access token format (e.g., ghp_....)

Ref:

• github/api: update personal access token format. Homebrew/brew#10847
• Update token format sindresorhus/notifier-for-github#246

Test

Tested the new regex with my revoked tokens

➜  jasper git:(fix-new-access-token-format) node
Welcome to Node.js v12.14.0.
Type ".help" for more information.
> 'db03ece8f912d2f5215ce24934003cc627b73019'.match(/^(?:[a-f0-9]{40}|ghp_\w{36,251})$/)
[
  'db03ece8f912d2f5215ce24934003cc627b73019',
  index: 0,
  input: 'db03ece8f912d2f5215ce24934003cc627b73019',
  groups: undefined
]
> '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'.match(/^(?:[a-f0-9]{40}|ghp_\w{36,251})$/)
[
  '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',
  index: 0,
  input: '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',
  groups: undefined
]

Confirmed it's working locally as well (npm run mac:run)

[limitusus]

Workaround until this PR is released for those who deleted old-formatted access token:

1. Launch Jasper app
2. Dev→Open Data Directory
3. Edit config.json (github.accessToken) and relaunch Jasper app.

[h13i32maru]

Thanks!