fix: Add CleanedBasePath to GithubSetupData (#2141)

[santelos]

Fixes: #2141

Background

Template for GithubAppSetupTemplate refers to the property CleanedBasePath of GithubSetupData struct that was undefined.

Changes:

• Property CleanedBasePath was added into GithubSetupData struct
• Property CleanedBasePath is assigned in server/controllers/github_app_controller.go with g.AtlantisURL.path
  Where g is GithubAppController struct

Test

• Tested locally with modified for local dev docker-compose run atlantis server.
  Was able to see http://localhost:4141/github-app/setup page

[davidham]

+1 to merge this

[dgokcin]

trying to set up atlantis for the first time, also having this issue. if this is the fix, +1 for the merge.

[davidham]

trying to set up atlantis for the first time, also having this issue. if this is the fix, +1 for the merge.

@dgokcin FWIW, I built an image from this branch, and when I ran it I was able to do the setup process, many thanks to @santelos for the fix.

[dgokcin]

@davidham I also worked arount the issue by running atlantis server manually and going to localhost:4141/github-app/setup to retrieve the github related values. Afterwards I replaced the localhosts with my atlantis server url and it worked.

[jamengual]

LGTM +1

[jamengual]

https://github.com/runatlantis/atlantis/releases/tag/v0.19.4-pre.20220513