Merge #4240

4240: Release 1.7.0: define the next Cardano SL version as 3.1.0 r=disassembler a=tatyanavych

## Description

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## Linked issue

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Co-authored-by: tatyanavych <[email protected]>

Author: iohk-bors[bot]

CHANGELOG.md

@@ -1,15 +1,20 @@
 # CHANGELOG
 
-## Unreleased
-- Correct change category in 3.0.3 and add section for unreleased changes [#4232](https://github.com/input-output-hk/cardano-sl/pull/4232)
+## Cardano SL 3.1.0
+
+### Features
 
-## Features
 - A new endpoint to calculate the walletid of a given mnemonic [#4237](https://github.com/input-output-hk/cardano-sl/pull/4237)
 
+### Fixes
+
+- Correct change category in 3.0.3 and add section for unreleased changes [#4232](https://github.com/input-output-hk/cardano-sl/pull/4232)
+
 ### Improvements
 
 - Configuration files and environments map moved to iohk-nix [#4227](https://github.com/input-output-hk/cardano-sl/pull/4227)
 
+
 ## Cardano SL 3.0.3
 
 ### Improvements