updated installation details with github package details

Author: MJRichardson

README.md

@@ -18,7 +18,47 @@ This provider will work with Java 11 and above.
 
 The Octopus OpenFeature provider for Java is currently published to [GitHub Packages](https://github.com/OctopusDeploy/openfeature-provider-java/packages/2528379). It will be published to the Maven Central repository soon.
 
-To add Maven package dependencies from GitHub Packages, you must configure an [authentication token](https://docs.github.com/en/packages/working-with-a-github-packages-registry/working-with-the-apache-maven-registry#authenticating-to-github-packages).
+To add Maven package dependencies from GitHub Packages, you will need to add a Maven repository (in either your `settings.xml` or `pom.xml`), and create a GitHub Personal Access Token (classic) with `read:packages` scope, and configure this to be used to authenticate. An example `settings.xml` is shown below:  
+
+```xml
+<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0
+                      http://maven.apache.org/xsd/settings-1.0.0.xsd">
+
+  <activeProfiles>
+    <activeProfile>github</activeProfile>
+  </activeProfiles>
+
+  <profiles>
+    <profile>
+      <id>github</id>
+      <repositories>
+        <repository>
+          <id>central</id>
+          <url>https://repo1.maven.org/maven2</url>
+        </repository>
+        <repository>
+          <id>github</id>
+          <url>https://maven.pkg.github.com/OctopusDeploy/openfeature-provider-java</url>
+          <snapshots>
+            <enabled>true</enabled>
+          </snapshots>
+        </repository>
+      </repositories>
+    </profile>
+  </profiles>
+
+  <servers>
+    <server>
+      <id>github</id>
+      <username>USERNAME</username>
+      <password>TOKEN</password>
+    </server>
+  </servers>
+</settings>
+```
+Read the GitHub docs for more information on [working with GitHub Packages as a Maven registry](https://docs.github.com/en/packages/working-with-a-github-packages-registry/working-with-the-apache-maven-registry#authenticating-to-github-packages).
 
 Once this is configured, you can add the Octopus OpenFeature provider as a dependency. The Maven example is shown below.