IS-506: Migrate GGS Whitelist Feature Flag to GB

[harishv7]

Problem

We are currently using env vars to rollout GGS implementation which requires a rebuild each time we change something.

Closes IS-506

Solution

Use GrowthBook feature flag. Introduces a new flag ggs_whitelisted_repos with a json structure of { "repos": string[] }. Please check the portal for more info.

Note: To be reviewed in conjunction with IS-310 and IS-312

Breaking Changes

• [ ] Yes - this PR contains breaking changes
  • Details ...
• [X] No - this PR is backwards compatible

Tests

• Ensure whitelisted repos are being read in from GB. To do so, can add a simple console.log in isRepoWhitelisted function of RepoService.
• Ensure all unit tests pass especially for RepoService.spec.ts

Deploy Notes

Please remove existing env var of WHITELISTED_GIT_SERVICE_REPOS from EB.

Deprecated environment variables:

• WHITELISTED_GIT_SERVICE_REPOS

New feature flags

• ggs_whitelisted_repos: ensure correct values are set on GB portal

[harishv7]

Implementation looks fine! It looks like it's only active on write/rollback route handlers though, so if we ever need to modify the content we're passing via GB we'll need to add this to the read route handler as well. We can just add this in as needed in future

@alexanderleegs sounds good. we can add in when we have a flag that touches the read route handler. for ggs, i have replaced all instances of isRepoWhitelisted with the feature flag