Specify heap dump path (#424)

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Fixes #423

gradle-sls-packaging/src/main/groovy/com/palantir/gradle/dist/service/tasks/LaunchConfigTask.java

@@ -58,6 +58,7 @@ public class LaunchConfigTask extends DefaultTask {
             "-XX:+CrashOnOutOfMemoryError",
             "-Djava.io.tmpdir=var/data/tmp",
             "-XX:ErrorFile=var/log/hs_err_pid%p.log",
+            "-XX:HeapDumpPath=var/log",
             // Set DNS cache TTL to 20s to account for systems such as RDS and other
             // AWS-managed systems that modify DNS records on failover.
             "-Dsun.net.inetaddr.ttl=20"

gradle-sls-packaging/src/test/groovy/com/palantir/gradle/dist/service/ServiceDistributionPluginTests.groovy

@@ -402,6 +402,7 @@ class ServiceDistributionPluginTests extends GradleIntegrationSpec {
                 '-XX:+CrashOnOutOfMemoryError',
                 '-Djava.io.tmpdir=var/data/tmp',
                 '-XX:ErrorFile=var/log/hs_err_pid%p.log',
+                '-XX:HeapDumpPath=var/log',
                 '-Dsun.net.inetaddr.ttl=20',
                 '-XX:+UseParallelOldGC',
                 '-Xmx4M',
@@ -424,6 +425,7 @@ class ServiceDistributionPluginTests extends GradleIntegrationSpec {
                 '-XX:+CrashOnOutOfMemoryError',
                 '-Djava.io.tmpdir=var/data/tmp',
                 '-XX:ErrorFile=var/log/hs_err_pid%p.log',
+                '-XX:HeapDumpPath=var/log',
                 '-Dsun.net.inetaddr.ttl=20',
                 '-Xmx4M',
                 '-Djavax.net.ssl.trustStore=truststore.jks'])
@@ -460,6 +462,7 @@ class ServiceDistributionPluginTests extends GradleIntegrationSpec {
                 '-XX:+CrashOnOutOfMemoryError',
                 '-Djava.io.tmpdir=var/data/tmp',
                 '-XX:ErrorFile=var/log/hs_err_pid%p.log',
+                '-XX:HeapDumpPath=var/log',
                 '-Dsun.net.inetaddr.ttl=20',
                 "-XX:+PrintGCDateStamps",
                 "-XX:+PrintGCDetails",