pgsql: Doc: Improve wording of multiple places in documentation

Doc: Improve wording of multiple places in documentation This has been found during its translation. Author: Liudmila Mantrova Discussion: https://postgr.es/m/caekd-mdjhv3bhgezu3muafjloaksoot86+whukku8_neijy...@mail.gmail.com Backpatch-through: 12 Branch -- master Details --- https://g

pgsql: Doc: Improve wording of multiple places in documentation

Doc: Improve wording of multiple places in documentation This has been found during its translation. Author: Liudmila Mantrova Discussion: https://postgr.es/m/caekd-mdjhv3bhgezu3muafjloaksoot86+whukku8_neijy...@mail.gmail.com Backpatch-through: 12 Branch -- REL_12_STABLE Details --- ht