Incorrect comment movement for groups of array items

I'd like to use comments to group sets of entries in an array together - the comment should be at the same level as the `-` for the entry; but yamlfmt keeps indenting or moving it, in consistent ways.

There also doesn't seem to be any docs saying what the expected indentation pattern is.

Testcase 1:
```
---
parent:
key:
- a: 1
b: 2

# Group comment
- &anchor
a: 2
b: 3
- a: 4
b: 5
```

Result 1:
```
$ yamlfmt -dry test1.yaml
test1.yaml:
--- ---
parent: parent:
key: key:
- a: 1 - a: 1
b: 2 b: 2
-
- # Group comment
- &anchor - &anchor
+ # Group comment
a: 2 a: 2
- b: 3 b: 3
- a: 4 - a: 4
- b: 5 b: 5
```

Testcase 2:
```
---
key:
#
- x: a
b: 1
- y: foo
b: bar
#

#
- z: ax
b: 1
- ab: something
b: 1
#
```

Result 2:
```
$ yamlfmt -dry test2.yaml
test2.yaml:
--- ---
key: key:
# #
- x: a - x: a
b: 1 b: 1
- y: foo - y: foo
b: bar b: bar
# #

# #
- z: ax - z: ax
b: 1 b: 1
- ab: something - ab: something
b: 1 b: 1
- # #
```