[bug] [yaml] list indent fix can result in invalid yaml or change the meaning of existing yaml

[michaele-blend]

Prettier 3.2.5
Playground link

--parser yaml

Input:

list:
- with:
    config-yml: |2
      hello: world

Output:

list:
  - with:
      config-yml: |2
      hello: world

Expected output:

list:
  - with:
      config-yml: |2
        hello: world

Why?

my expectation is that prettier does not change the meaning of a yaml document.
the list indent fix here changes the meaning of the document, the config-yml values are promoted, and with gains new keys.
this can also result in invalid yaml documents, if the multi-line string is not also valid yaml. for instance,

list:
- with:
    config-yml: |2
      hello

will be transformed into

list:
  - with:
      config-yml: |2
      hello

which is not a valid yaml document.