YAML: Preserve blank lines in comments (#8356)

* YAML: Fix ugly comments

* Add changelog

* Use common utils

changelog_unreleased/yaml/pr-8356.md

@@ -0,0 +1,54 @@
+#### Preserve blank lines in comments ([#8356](https://github.com/prettier/prettier/pull/8356) by [@fisker](https://github.com/fisker))
+
+<!-- prettier-ignore -->
+```yaml
+# Input
+a:
+  - a: a
+
+  # - b: b
+
+  # - c: c
+
+  - d: d
+
+
+b:
+  - a: a
+
+  # - b: b
+
+  # - c: c
+
+# Prettier stable
+a:
+  - a: a
+
+  # - b: b
+
+  # - c: c
+
+  - d: d
+
+b:
+  - a: a
+  # - b: b
+  # - c: c
+
+// Prettier master
+a:
+  - a: a
+
+  # - b: b
+
+  # - c: c
+
+  - d: d
+
+b:
+  - a: a
+
+  # - b: b
+
+  # - c: c
+```