Common - Remove feature flag (#15371)

To be done in an other PR, move graphql-query-runner handlers in
common-api-query-runner folder (+ renaming + typing improvments)


Fixes : 
- totalCount on findMany (Rest)
- getAllSelectedFields did not handle composite field (Rest)
- issue with endCursor (Rest)
- args processing for updateOne and createOne (Rest + Gql)
- fix findDuplicates (Gql)

packages/twenty-server/src/engine/workspace-manager/dev-seeder/core/utils/seed-feature-flags.util.ts

@@ -61,11 +61,6 @@ export const seedFeatureFlags = async (
         workspaceId: workspaceId,
         value: workspaceId === SEED_APPLE_WORKSPACE_ID,
       },
-      {
-        key: FeatureFlagKey.IS_COMMON_API_ENABLED,
-        workspaceId: workspaceId,
-        value: false,
-      },
       {
         key: FeatureFlagKey.IS_PAGE_LAYOUT_ENABLED,
         workspaceId: workspaceId,