Update Observability Kit Agent download link to 3.2.0 (#4662)

Co-authored-by: Mikhail Shabarov <[email protected]>

Author: heruan

articles/tools/observability/getting-started.adoc

@@ -65,7 +65,7 @@ The Agent is based on the OpenTelemetry standard and is packaged as a `.jar` fil
 [IMPORTANT]
 The Agent cannot be used as a dependency. It must be downloaded separately.
 
-link:https://repo1.maven.org/maven2/com/vaadin/observability-kit-agent/2.2.1/observability-kit-agent-2.2.1.jar[Download Observability Kit Agent, role="button secondary water"]
+link:https://repo1.maven.org/maven2/com/vaadin/observability-kit-agent/3.2.0/observability-kit-agent-3.2.0.jar[Download Observability Kit Agent, role="button secondary water"]
 
 Once the Agent has finished downloading to the project directory, it needs to be configured to export telemetry to one or more observability tools. In this guide, traces are exported to Jaeger; metrics are sent to Prometheus. To do this, create an [filename]`agent.properties` file in the project directory with the following content: