Increase JVM metaspace size

The public workflow on macOS runners are hanging[1]. This is due to an
upstream bug in the Dokka plugin[2].

[1] https://github.com/michaelbull/kotlin-result/runs/4011488028?check_suite_focus=true
[2] https://github.com/Kotlin/dokka/issues/1405

gradle.properties

@@ -1,6 +1,7 @@
-kotlin.code.style=official
-
 group=com.michael-bull.kotlin-result
 version=1.1.13-SNAPSHOT
 
+kotlin.code.style=official
 kotlin.native.ignoreDisabledTargets=true
+
+org.gradle.jvmargs=-XX:MaxMetaspaceSize=1g