[Feature flag] Rollout of `releases_index_apollo_client`

Summary

This issue is to rollout the conversion of the Releases page to use Apollo Client in production. It's currently behind the releases_index_apollo_client feature flag.

Owners

• Team: ~"group::release"
• Most appropriate slack channel to reach out to: #s_release
• Best individual to reach out to: @nfriend
• PM: @kbychu

The Rollout Plan

• Enable in production for gitlab-org/gitlab
• Update the feature flag to be enabled by default
• Remove the feature flag

Testing Groups/Projects/Users

• gitlab-org/gitlab project

Expectations

What are we expecting to happen?

No user-facing changes.

What might happen if this goes wrong?

The Releases page might break. It may throw errors, or it may fail to render entirely (and just show blank page).

What can we monitor to detect problems with this?

This is a purely frontend change, so any problems should show up in Sentry.

Rollback Steps

• This feature can be disabled by running the following Chatops command:

/chatops run feature set releases_index_apollo_client false