Unable to preserve YAML formatting while using yq

[gravops]

I am trying to update one certificate inside an argo cd app project. While I am doing so it is not preserving the YAML format and making changes.

1. First I am fetching only the values part from the file and store in tmp-app.yaml
   yq '.spec.source.helm.values' app.yaml > tmp-app.yaml

2. Then update the certificate value in tmp-app.yaml from a variable
   yq ".oidc.caPEM |= (from_yaml | \"${ca_cert_content//$'\n'/\\n}\" | to_yaml)" -i tmp-app.yaml

3. Then I am loading the updated file back into the original file.
   yq '.spec.source.helm.values = load("tmp-app.yaml")' -i app.yaml

Now I am facing issue in step 2 and 3.

Issues:
In step 2 all the blank lines are getting pruned and yq in increasing the indent as well.
In step 3 when i load the file it is removing (|-) from values.

My app.yaml format:
apiVersion: argoproj.io/v1alpha1 kind: Application metadata: spec: source: values: |- oidc: caPEM: |

app.yaml after update:
apiVersion: argoproj.io/v1alpha1 kind: Application metadata: spec: source: values: oidc: caPEM: |

I want to preserver '|-' after values and also any new line present under values.