Update changelog with TimescaleDB v2.25 features

[brandonpurcell-dev]

Added details about TimescaleDB v2.25 features and improvements, including faster queries on compressed data, continuous aggregates enhancements, and quality of life updates. Updated the changelog to reflect new features and automation updates.

2.25 was delayed to the cloud until we could get 2.25.1 out so it went live last week.

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[github-actions]

Allow 10 minutes from last push for the staging site to build. If the link doesn't work, try using incognito mode instead. For internal reviewers, check web-documentation repo actions for staging build status. Link to build for this PR: http://docs-dev.timescale.com/docs-brandonpurcell-dev-tsdbv225

[atovpeko]

Moved it into its own entry, as it properly deserves :-) Hope that's fine.