Remove unneeded argument and add parallel forks for unit tests (#779)

app/build.gradle.kts

@@ -276,7 +276,7 @@ tasks {
     withType<Test> {
         useJUnitPlatform()
         maxHeapSize = "4g"
-        jvmArgs = listOf("-XX:MaxMetaspaceSize=512m")
+        maxParallelForks = Runtime.getRuntime().availableProcessors()
     }
 }
 

gradle.properties

@@ -6,3 +6,4 @@ android.useAndroidX=true
 kotlin.code.style=official
 
 org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8
+org.gradle.parallel=true