Merge pull request #924 from mkurz/scala-steward_patch-group

Group Scala Steward patch updates into single PR

.scala-steward.conf

@@ -1,10 +1,11 @@
-pullRequests.frequency = "@weekly"
-
-updates.pin  = [
-]
+pullRequests.frequency = "@monthly"
 
 commits.message = "${artifactName} ${nextVersion} (was ${currentVersion})"
 
+pullRequests.grouping = [
+  { name = "patches", "title" = "Patch updates", "filter" = [{"version" = "patch"}] }
+]
+
 updates.ignore = [
   // these will get updated along with jackson-core, so no need to update them separately
   { groupId = "com.fasterxml.jackson.core", artifactId = "jackson-annotations" }