Fix gh_create_issue input formatting

Signed-off-by: Daniel Weiße <[email protected]>

.github/actions/gh_create_issue/action.yml

@@ -39,7 +39,7 @@ inputs:
     description: "The template to use for the issue."
     required: false
   fields:
-    description: "A JSON object containing the fields to use for the issue."
+    description: "A YAML or JSON object containing the fields to use for the issue."
     required: false
 
 outputs:
@@ -60,5 +60,9 @@ runs:
         cat << EOF | tee inputs.json
         ${{ toJSON(inputs) }}
         EOF
+
+        yq -oj -iP ". += { \"fields\": $(echo "${{ inputs.fields }}" | yq -oj -P '.' -) }" inputs.json
+
+        cat inputs.json
         out=$(./.github/actions/gh_create_issue/create_issue.sh inputs.json)
         echo "issue-url=${out}" | tee -a "$GITHUB_OUTPUT"