Update elastic-apm-agent dependency to use Java 8 variant

This variant has updated log4j dependency.

Author: jozala

modules/apm/build.gradle

@@ -20,7 +20,7 @@ dependencies {
   implementation "io.opentelemetry:opentelemetry-api:${otelVersion}"
   implementation "io.opentelemetry:opentelemetry-context:${otelVersion}"
   implementation "io.opentelemetry:opentelemetry-semconv:${otelSemconvVersion}"
-  runtimeOnly    "co.elastic.apm:elastic-apm-agent:1.55.0"
+  runtimeOnly    "co.elastic.apm:elastic-apm-agent-java8:1.55.0"
 
   javaRestTestImplementation project(':modules:apm')
   javaRestTestImplementation project(':test:framework')