Bump metrics-core from 4.1.3 to 4.1.5

Bumps [metrics-core](https://github.com/dropwizard/metrics) from 4.1.3 to 4.1.5.
- [Release notes](https://github.com/dropwizard/metrics/releases)
- [Commits](dropwizard/metrics@v4.1.3...v4.1.5)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

micrometer-registry-ganglia/build.gradle

@@ -14,7 +14,7 @@ dependencies {
     testCompile "io.micronaut:micronaut-inject-groovy"
     annotationProcessor "io.micronaut:micronaut-inject-java"
     testRuntime "io.micronaut:micronaut-http-server-netty"
-    testRuntime "io.dropwizard.metrics:metrics-core:4.1.3"
+    testRuntime "io.dropwizard.metrics:metrics-core:4.1.5"
     testCompile "io.micronaut:micronaut-http-client"
 }