Add Kover plugin (#1733)

Co-authored-by: Sergey.Shanshin <sergey.shanshin@jetbrains.com>
diff --git a/gradle.properties b/gradle.properties
index aa4d579..0514864 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -18,6 +18,9 @@
 validator_version=0.7.1
 knit_version=0.2.2
 coroutines_version=1.3.9
+kover_version=0.3.0
+
+kover.enabled=true
 
 kotlin.mpp.enableGranularSourceSetsMetadata=true
 kotlin.mpp.enableCompatibilityMetadataVariant=true