doc fix: use OTel instead of Brave

fixes gh-92

Author: jonatan-ivanov

docs/src/main/asciidoc/getting-started.adoc

@@ -14,11 +14,11 @@ We then walk you through building your first {project-full-name} application, di
 Spring Cloud Sleuth OTel provides integration with https://opentelemetry.io[OpenTelemetry SDK].
 
 [[getting-started-first-application]]
-== Developing Your First Spring Cloud sleuth-based Application
+== Developing Your First Spring Cloud Sleuth OTel based Application
 
 This section describes how to develop a small “Hello World!” web application that highlights some of Spring Cloud Sleuth’s key features.
 We use Maven to build this project, since most IDEs support it.
-As the tracer implementation we'll use https://github.com/openzipkin/brave[OpenZipkin Brave].
+As the tracer implementation we'll use https://github.com/open-telemetry/opentelemetry-java[OpenTelemetry].
 
 [TIP]
 ====
@@ -237,4 +237,4 @@ We also have {project-full-name}-specific "`<<howto.adoc#howto, how-to>>`" refer
 
 Otherwise, the next logical step is to read <<using.adoc#using, Using {project-full-name}>>.
 If you are really impatient, you could also jump ahead and read about
-<<project-features.adoc#project-features, {project-full-name} features>>.
+<<project-features.adoc#project-features, {project-full-name} features>>.