Merge pull request #5574 from nextcloud/dependabot/gradle/kotlin_version-1.3.70

Bump kotlin_version from 1.3.61 to 1.3.70

build.gradle

@@ -7,7 +7,7 @@
 import com.github.spotbugs.SpotBugsTask
 
 buildscript {
-    ext.kotlin_version = '1.3.61'
+    ext.kotlin_version = '1.3.70'
     repositories {
         google()
         jcenter()