oracle-v2.28.0

What's Changed

• chore: update readme with deployment steps by @cctdaniel in #397
• chore: cleanup permissions by @guibescos in #396
• refactor: move upd_twap from upd_aggregate to rust upd_price by @cctdaniel in #398
• refactor: remove pythnet feature flag by @cctdaniel in #399
• feat: aggregate in the same slot by @cctdaniel in #394

Full Changelog: oracle-v2.27.0...oracle-v2.28.0