Bump to version 2.9.0 (#4293)

* Add 2.9.0 to CHANGELOG.md

* Bump version 2.8.0 to 2.9.0

* Update lockfiles for release 2.9.0

---------

Co-authored-by: Oleg Pudeyev <[email protected]>

Author: p-datadog

CHANGELOG.md

@@ -2,6 +2,28 @@
 
 ## [Unreleased]
 
+## [2.9.0] - 2025-01-15
+
+### Added
+
+* Core: add support for Ruby 3.4 ([#4249][])
+* Integrations: add a new option for `ActiveSupport` to disable adding the `cache_key` as a Span Tag with the `cache_key_enabled` option ([#4022][])
+
+### Changed
+
+* Dynamic instrumentation: move DI preloading to `datadog/di/preload` ([#4288][])
+* Dynamic instrumentation: dd-trace-rb now reports whether dynamic instrumentation is enabled in startup summary report ([#4285][])
+* Dynamic instrumentation: improve loading of DI components ([#4272][], [#4239][])
+* Dynamic instrumentation: logging of internal conditions is now done on debug level ([#4266][])
+* Dynamic instrumentation: report instrumentation error for line probes when the target file is loaded but not in code tracker registry ([#4208][])
+* Profiling: require datadog-ruby_core_source >= 3.3.7 to ensure Ruby 3.4 support ([#4228][])
+
+### Fixed
+
+* Core: fix a crash in crashtracker when agent hostname is an IPv6 address ([#4237][])
+* Profiling: fix allocation profiling + otel tracing causing Ruby crash ([#4240][])
+* Profiling: fix profiling warnings being really hard to silence ([#4232][])
+
 ## [2.8.0] - 2024-12-10
 
 ### Added
@@ -3057,7 +3079,8 @@ Release notes: https://github.com/DataDog/dd-trace-rb/releases/tag/v0.3.1
 Git diff: https://github.com/DataDog/dd-trace-rb/compare/v0.3.0...v0.3.1
 
 
-[Unreleased]: https://github.com/DataDog/dd-trace-rb/compare/v2.8.0...master
+[Unreleased]: https://github.com/DataDog/dd-trace-rb/compare/v2.9.0...master
+[2.9.0]: https://github.com/DataDog/dd-trace-rb/compare/v2.8.0...v2.9.0
 [2.8.0]: https://github.com/DataDog/dd-trace-rb/compare/v2.7.1...v2.8.0
 [2.7.0]: https://github.com/DataDog/dd-trace-rb/compare/v2.6.0...v2.7.0
 [2.6.0]: https://github.com/DataDog/dd-trace-rb/compare/v2.5.0...v2.6.0
@@ -4499,6 +4522,7 @@ Git diff: https://github.com/DataDog/dd-trace-rb/compare/v0.3.0...v0.3.1
 [#3997]: https://github.com/DataDog/dd-trace-rb/issues/3997
 [#4014]: https://github.com/DataDog/dd-trace-rb/issues/4014
 [#4020]: https://github.com/DataDog/dd-trace-rb/issues/4020
+[#4022]: https://github.com/DataDog/dd-trace-rb/issues/4022
 [#4024]: https://github.com/DataDog/dd-trace-rb/issues/4024
 [#4027]: https://github.com/DataDog/dd-trace-rb/issues/4027
 [#4033]: https://github.com/DataDog/dd-trace-rb/issues/4033
@@ -4519,6 +4543,17 @@ Git diff: https://github.com/DataDog/dd-trace-rb/compare/v0.3.0...v0.3.1
 [#4195]: https://github.com/DataDog/dd-trace-rb/issues/4195
 [#4196]: https://github.com/DataDog/dd-trace-rb/issues/4196
 [#4197]: https://github.com/DataDog/dd-trace-rb/issues/4197
+[#4208]: https://github.com/DataDog/dd-trace-rb/issues/4208
+[#4228]: https://github.com/DataDog/dd-trace-rb/issues/4228
+[#4232]: https://github.com/DataDog/dd-trace-rb/issues/4232
+[#4237]: https://github.com/DataDog/dd-trace-rb/issues/4237
+[#4239]: https://github.com/DataDog/dd-trace-rb/issues/4239
+[#4240]: https://github.com/DataDog/dd-trace-rb/issues/4240
+[#4249]: https://github.com/DataDog/dd-trace-rb/issues/4249
+[#4266]: https://github.com/DataDog/dd-trace-rb/issues/4266
+[#4272]: https://github.com/DataDog/dd-trace-rb/issues/4272
+[#4285]: https://github.com/DataDog/dd-trace-rb/issues/4285
+[#4288]: https://github.com/DataDog/dd-trace-rb/issues/4288
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