The `Δ` caused issue with other infrastructure, and we are temporarily
changing it to `ɵɵ`.
This commit also patches ts_api_guardian_test and AIO to understand `ɵɵ`.
PR Close#29850
* doc(public_api): change description
Benchpress has been moved to angular/angular in modules/@angular/benchpress
* docs(public_api): change description
Here means 'other projects',like angular-cli, Angular Material. And as we know, benchpress project has been moved to angular/angular in modules/@angular/benchpress. It should not be 'other projects'.