Revert "IGNITE-20200 Fix Gradle non-zero exit code on test failure (#2442)"

This reverts commit 027bdd16819ff8a6d811b6cba836652b28592e0b.
diff --git a/buildscripts/java-core.gradle b/buildscripts/java-core.gradle
index 52c7251..36d414e 100644
--- a/buildscripts/java-core.gradle
+++ b/buildscripts/java-core.gradle
@@ -29,8 +29,6 @@
 }
 
 test {
-    ignoreFailures = true
-
     finalizedBy(jacocoTestReport)
 }