CloudFlare Workers seems to only see Build Variables & Secrets on main branch on some projects

### Describe the Bug

CloudFlare Workers - Build Variables & Secrets don't appear consistently in build jobs.

### Expected Behavior

I have an NPM_TOKEN registered in multiple workers so that during the build phase, a private NPM module can be installed. This works in some workers but not others.

### Steps to Reproduce

1. If you visit https://dash.cloudflare.com/aa1e065f6f6da808def1292426bed033/workers/services/view/greg-l-turnquist/production/settings, you can see clearly that NPM_TOKEN is set. And if you dig in, this value has been set for some time.
2. In the Deployments version history, this works just fine WHEN you build on main branch. However, any builds NOT on main branch fail due to NPM_TOKEN not being visible.
3. This implies that setting NPM_TOKEN doesn't end up being universal.

Contrast this with another CloudFlare Worker, that seems to build just fine.

1. If you check out https://dash.cloudflare.com/aa1e065f6f6da808def1292426bed033/workers/services/view/pro-coder-io/production/settings, it also has NPM_TOKEN configured. And it builds fine on main branch.
2. But it ALSO builds fine on branch builds as recently as 15 days ago => https://dash.cloudflare.com/aa1e065f6f6da808def1292426bed033/workers/services/view/pro-coder-io/production/builds/8e058b56-e576-4f3c-9452-46f545c12acf

This is wholly inconsistent behavior, implying something under the hood has changed.

Comienza comparando la configuración de Cloudflare Workers y los historiales de despliegue enlazados en el informe para greg-l-turnquist y pro-coder-io. Reproduce las compilaciones en ramas main y no-main, comprobando si el NPM_TOKEN configurado está disponible durante cada compilación. Se considerará completado cuando se haya reproducido el comportamiento dependiente de la rama y se haya identificado su causa o documentado con evidencias de las compilaciones.

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