Updating release notes for 4.2.7.0

Author: foundationdb-ci

docs/sphinx/source/ReleaseNotes.md

@@ -7,6 +7,50 @@ As the [versioning guide](Versioning.md) details, it cannot always be determined
 
 ## 4.2
 
+### 4.2.7.0
+
+<h4> Breaking Changes </h4>
+
+* Remove deprecated IndexingByRecords module - [PR #3312](https://github.com/FoundationDB/fdb-record-layer/pull/3312)
+<h4> New Features </h4>
+
+* Add support for record validation - [PR #3314](https://github.com/FoundationDB/fdb-record-layer/pull/3314)
+* Transition FormatVersion from constants to an enum - [PR #3304](https://github.com/FoundationDB/fdb-record-layer/pull/3304)
+* Prepare the Cascades planner for multi-stage planning by enabling property computation on arbitrary expressions - [PR #3321](https://github.com/FoundationDB/fdb-record-layer/pull/3321)
+* Extra cleanup for the index scrubbing code - [PR #3317](https://github.com/FoundationDB/fdb-record-layer/pull/3317)
+<h4> Bug Fixes </h4>
+
+* query uses grouping index with Is_Null predicate  - [PR #3327](https://github.com/FoundationDB/fdb-record-layer/pull/3327)
+* fix for pull up of null-on-empty bug - [PR #3323](https://github.com/FoundationDB/fdb-record-layer/pull/3323)
+* Fix potential NPE due to exception not having an underlying message - [PR #3302](https://github.com/FoundationDB/fdb-record-layer/pull/3302)
+* Prevent setting the format version to an unsupported version - [PR #3309](https://github.com/FoundationDB/fdb-record-layer/pull/3309)
+
+<details>
+<summary>
+
+<h4> Build/Test/Documentation/Style Improvements (click to expand) </h4>
+
+</summary>
+
+* Remove jfrog from repository list - [PR #3339](https://github.com/FoundationDB/fdb-record-layer/pull/3339)
+* Fix broken gradle task: testShadowJar - [PR #3320](https://github.com/FoundationDB/fdb-record-layer/pull/3320)
+* Upgrade to gradle 8 - [PR #3316](https://github.com/FoundationDB/fdb-record-layer/pull/3316)
+
+</details>
+
+
+**[Full Changelog (4.2.6.0...4.2.7.0)](https://github.com/FoundationDB/fdb-record-layer/compare/4.2.6.0...4.2.7.0)**
+
+#### Mixed Mode Test Results
+
+Mixed mode testing run against the following previous versions:
+
+❌`4.1.6.0`, ❌`4.1.8.0`, ✅`4.1.9.0`, ✅`4.1.10.0`, ✅`4.2.2.0`, ✅`4.2.2.1`, ❌`4.2.3.0`, ❌`4.2.4.0`, ✅`4.2.5.0`, ✅`4.2.6.0`
+
+[See full test run](https://github.com/FoundationDB/fdb-record-layer/actions/runs/14864688455)
+
+
+
 ### 4.2.6.0
 
 <h4> Breaking Changes </h4>