chore: Updating README.md and CONTRIBUTING.md to include details about semantic versioning (#3112)

* chore: Updating README.md and CONTRIBUTING.md to include details about semantic versioning

* updating contribution.md to update legend list

Author: harsh62

CONTRIBUTING.md

@@ -4,6 +4,8 @@ Thank you for your interest in contributing to our project! <3 Whether it's a bu
 
 - [History & Ethos](#our-history-and-ethos)
   - [Our Design](#our-design)
+- [Semantic versioning](#semantic-versioning)
+  - [Semantic versioning and enumeration cases](#semantic-versioning-and-enumeration-cases)
 - [Getting Started](#getting-started)
 - [Testing](#testing)
 - [Tools](#tools)
@@ -27,6 +29,17 @@ Thank you for your interest in contributing to our project! <3 Whether it's a bu
 
 For a brief history and our ethos/design philosophy around the Amplify project please refer to this [document](/ETHOS.md).
 
+## Semantic versioning
+
+We follow [semantic versioning](https://semver.org/) for our releases.
+
+### Semantic versioning and enumeration cases
+
+When Amplify adds a new enumeration value, we will publish a new **minor** version
+of the library.
+
+Applications that evaluate all members of an enumeration using a `switch` statement can add a `default` case to prevent new cases from causing compile warnings or errors.
+
 ## Getting Started
 
 To get started with the Amplify Library for Swift, first make sure you have Xcode 13.4 or later installed.

README.md

@@ -37,6 +37,17 @@ The Amplify Library for Swift is layered on the [AWS SDK for Swift](https://aws.
 > To use Amplify Swift with visionOS, you'll need to target the `visionos-preview` branch.
 > For more information, see [Platform Support](https://github.com/aws-amplify/amplify-swift/tree/visionos-preview#platform-support) on the `visionos-preview` branch.
 
+## Semantic versioning
+
+We follow [semantic versioning](https://semver.org/) for our releases.
+
+### Semantic versioning and enumeration cases
+
+When Amplify adds a new enumeration value, we will publish a new **minor** version
+of the library.
+
+Applications that evaluate all members of an enumeration using a `switch` statement can add a `default` case to prevent new cases from causing compile warnings or errors.
+
 ## License
 
 This library is licensed under the Apache 2.0 License.