Capture core dump files from tests

When running Elasticsearch in tests we occassionally have JDK crashes.
It's important to capture the state of the JVM at the time of the crash.
We currently capture the hs_err_pid file for the crash, but the
resulting core file exists in a directory that is no captured. This
commit adjusts the capture patterns to also get core files.

Author: rjernst

build-tools-internal/src/main/java/org/elasticsearch/gradle/internal/ElasticsearchBuildCompletePlugin.java

@@ -110,6 +110,8 @@ private List<File> resolveProjectLogs(File projectDir) {
         projectDirFiles.include("**/build/testrun/*/temp/**");
         projectDirFiles.include("**/build/**/hs_err_pid*.log");
         projectDirFiles.include("**/build/**/replay_pid*.log");
+        // core dump files are in the working directory of the installation, which is not project specific
+        projectDirFiles.include("distribution/**/build/install/*/core.*");
         projectDirFiles.exclude("**/build/testclusters/**/data/**");
         projectDirFiles.exclude("**/build/testclusters/**/distro/**");
         projectDirFiles.exclude("**/build/testclusters/**/repo/**");