WordPress.org profiles: fix the credits API to correctly reflect release squads

I was on the release squads for WP 5.9 to 6.6 yet my profile just shows one of those releases (6.0):

Digging into this, it's due to the Credits API and its limitations. In talking to @desrosj he helped clarify that the profile code is only showing those with a label in the core-developers key as part of the squad whereas starting in 6.8 we returned to noting everyone on the squad. For WordPress 6.0, the one release it has me as, I am listed as being a part of the Core Developers. Jonathan noted that we could retroactively add labels, but the issue is the strings are not guaranteed to be present or translated in older versions.

IMO, until this is fixed, I think it's worth manually getting right considering it's really helpful to see people's release experience, especially when evaluating folks for release squads.