GitHub Action for reading JSON file - terraform

Question

I would like to write a GH action that uses JSON data as a parameter.
The plan is to save the Terraform output as a JSON file in one step and access it in the sequential step.
name: Test and Terraform
on:
push:
branches: [ main ]
pull_request:
branches: [ main ]
jobs:
Unit-Tests:
...
Terraform:
runs-on: ubuntu-18.04
needs: [ Unit-Tests, S3-Sync ]
steps:
...
- name: Terraform Apply
if: github.ref == 'refs/heads/main' && github.event_name == 'push'
run: |
cd terraform
terraform apply -auto-approve
terraform output --json > output.json
- name: Set Terraform Output
id: output
if: github.ref == 'refs/heads/main' && github.event_name == 'push'
run: |
content=`cat ./terraform/output.json`
# the following lines are only required for multi line json
content="${content//'%'/'%25'}"
content="${content//$'\n'/'%0A'}"
content="${content//$'\r'/'%0D'}"
# end of optional handling for multi line json
echo "::set-output name=terraform::$content"
- name: Gatsby Cloud Sync
if: github.ref == 'refs/heads/main' && github.event_name == 'push'
run: |
echo "${{fromJson(steps.output.outputs.terraform)}}"
The current error I get with this is that the final step is formatted improperly.
The template is not valid. .github/workflows/main.yml (Line: 154, Col: 14): Unexpected character encountered while parsing value: c. Path '', line 1, position 1.
How is the last step, Gatsby Cloud Sync, formatted incorrectly?