documentation

Pull request #1950: feature/ZBX-25057-7.0-D. clarified ambiguities on "Upgrade notes for 7.0.0" and "Database upgrade to primary keys" pages.

Merge in WEB/documentation from feature/ZBX-25057-7.0-D to release/7.0

* commit '281e984d686a29a88e4aafb77e10a00cd60e423f':
  [ZBX-25057] added helpful note (upgrading to primary keys can be time-consuming and resource-intensive)
  [ZBX-25057] removed unnecessary instructions for TimescaleDB with compression
  [ZBX-25057] clarified ambiguities on "Upgrade notes for 7.0.0" and "Database upgrade to primary keys" pages (fixed minor shortcomings)
  [ZBX-25057] clarified ambiguities on "Upgrade notes for 7.0.0" and "Database upgrade to primary keys" pages (fixed minor shortcomings)
  ZBX-25057] clarified ambiguities on "Upgrade notes for 7.0.0" and "Database upgrade to primary keys" pages
  [ZBX-25057] clarified ambiguities on "Upgrade notes for 7.0.0" and "Database upgrade to primary keys" pages
  [ZBX-25057] clarified ambiguities on "Upgrade notes for 7.0.0" and "Database upgrade to primary keys" pages
  [ZBX-25057] clarified ambiguities on "Upgrade notes for 7.0.0" and "Database upgrade to primary keys" pages