[FSSDK-9984] chore: prepare for release v3.1.0 (#257)

* build: increment the semantic version

* docs: update changelog.md

* docs: PR review adjustment to CHANGELOG

---------

Co-authored-by: Mike Chu <michael.chu@optmizely.com>

CHANGELOG.md

@@ -1,5 +1,17 @@
 # Changelog
 
+## [3.1.0] - April 9, 2024
+
+### Bug Fixes
+- Error initializing client. The core client or user promise(s) rejected.
+ ([#255](https://github.com/optimizely/react-sdk/pull/255))
+- Unable to determine if feature "{your-feature-key}" is enabled because User ID is not set([#255](https://github.com/optimizely/react-sdk/pull/255))
+
+### Changed
+- Bumped Optimizely JS SDK version in use ([#255](https://github.com/optimizely/react-sdk/pull/255))
+- Resolve dependabot dependency vulnerabilities ([#245](https://github.com/optimizely/react-sdk/pull/245), [#247](https://github.com/optimizely/react-sdk/pull/247), [#248](https://github.com/optimizely/react-sdk/pull/248), [#251](https://github.com/optimizely/react-sdk/pull/251), [#253](https://github.com/optimizely/react-sdk/pull/253))
+- Add node versions during testing ([#249](https://github.com/optimizely/react-sdk/pull/249))
+
 ## [3.0.1] - February 27, 2024
 
 ### Changed

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@optimizely/react-sdk",
-  "version": "3.0.1",
+  "version": "3.1.0",
   "description": "React SDK for Optimizely Feature Experimentation, Optimizely Full Stack (legacy), and Optimizely Rollouts",
   "homepage": "https://github.com/optimizely/react-sdk",
   "repository": "https://github.com/optimizely/react-sdk",

src/client.spec.ts

@@ -127,7 +127,7 @@ describe('ReactSDKClient', () => {
     expect(createInstanceSpy).toBeCalledWith({
       ...config,
       clientEngine: 'react-sdk',
-      clientVersion: '3.0.1',
+      clientVersion: '3.1.0',
     });
   });
 

src/client.ts

@@ -47,7 +47,7 @@ export interface OnReadyResult extends ResolveResult {
 }
 
 const REACT_SDK_CLIENT_ENGINE = 'react-sdk';
-const REACT_SDK_CLIENT_VERSION = '3.0.1';
+const REACT_SDK_CLIENT_VERSION = '3.1.0';
 
 export const DefaultUser: UserInfo = {
   id: null,