Flip apiref productionAlias to true, trim cutover docs from README #28604

Job	Run time
Compiler Tests	2m 2s
other-tests / Check PHAR checksum	11s
integration-tests / Check PHAR checksum	13s
extension-tests / Check PHAR checksum	13s
Commit PHAR	0s
Download base SHA PHAR	0s
PHAR Prefix Diff	0s
Checksum PHAR	0s
other-tests / Other Tests	0s
extension-tests / ${{ matrix.extension-name }} (${{ matrix.php-version }}) ${{ matrix.script }}	0s
integration-tests / Integration - ${{ matrix.name }}	0s
integration-tests / Integration - ${{ matrix.repo }}	0s
integration-tests / PMMP Tests	0s
integration-tests / Integration - Update baselines	0s
	2m 39s

Provide feedback