Describe the bug
vault-action v2.1.2 breaks the secrets that are stored as json, for example json web token keys, because the values are now parsed as json instead of a string REF.

To Reproduce
Example secret that is stored as json:

{ "kty": "RSA", "n": ...

Was in v2.1.1 passed to the application in the correct JSON format as

{ "kty": "RSA", "n": ...

In v2.1.2 it is passed to the application as JavaScript object representation, which is not valid JSON:

{ kty: RSA, n: ...

This results in a fatal error in the application due to invalid formatting.

Expected behavior
The secrets in JSON format should not be modified and passed to the application in valid JSON format.