[Bugfix] Remove blocks on calls to partners api

[jantnovi]

WHY are these changes introduced?

Fixes issues-develop/issues/21679

WHAT is this pull request doing?

Reverting changes we shipped that block the Partners API, as we still need to use it for dashboard extension migration.

How to test your changes?

Run shopify app deploy on any app with a dashboard managed extension that needs to be migrated to the new platform.

Checklist

• I've considered possible cross-platform impacts (Mac, Linux, Windows)
• I've considered possible documentation changes
  • I'll have to look for references for these env vars

[github-actions]

We detected some changes at packages/*/src and there are no updates in the .changeset.
If the changes are user-facing, run pnpm changeset add to track your changes and include them in the next release CHANGELOG.

Caution

DO NOT create changesets for features which you do not wish to be included in the public changelog of the next CLI release.

[github-actions]

Differences in type declarations

We detected differences in the type declarations generated by Typescript for this branch compared to the baseline ('main' branch). Please, review them to ensure they are backward-compatible. Here are some important things to keep in mind:

• Some seemingly private modules might be re-exported through public modules.
• If the branch is behind main you might see odd diffs, rebase main into this branch.

New type declarations

We found no new type declarations in this PR

Existing type declarations

packages/cli-kit/dist/private/node/constants.d.ts

@@ -28,8 +28,6 @@ export declare const environmentVariables: {
     otelURL: string;
     themeKitAccessDomain: string;
     json: string;
-    neverUsePartnersApi: string;
-    usePartnersApi: string;
     skipNetworkLevelRetry: string;
     maxRequestTimeForNetworkCalls: string;
 };

packages/cli-kit/dist/public/node/environment.d.ts

@@ -50,12 +50,6 @@ export declare function getIdentityTokenInformation(): {
  * @returns True if the JSON output is enabled, false otherwise.
  */
 export declare function jsonOutputEnabled(environment?: NodeJS.ProcessEnv): boolean;
-/**
- * If true, the CLI should not use the Partners API.
- *
- * @returns True when the CLI should not use the Partners API.
- */
-export declare function blockPartnersAccess(): boolean;
 /**
  * If true, the CLI should not use the network level retry.
  *

[gonzaloriestra]

Closing in favor of #6708