Fix JSON stringification

Author: alukach

lib/stac-auth-proxy/index.ts

@@ -38,10 +38,12 @@ export class StacAuthProxyLambdaRuntime extends Construct {
         // swagger-ui config
         OPENAPI_SPEC_ENDPOINT: "/api",
         SWAGGER_UI_ENDPOINT: "/api.html",
-        SWAGGER_UI_INIT_OAUTH: props.stacApiClientId && JSON.stringify({
-          clientId: props.stacApiClientId,
-          usePkceWithAuthorizationCodeGrant: true,
-        }),
+        SWAGGER_UI_INIT_OAUTH:
+          props.stacApiClientId &&
+          cdk.Stack.of(this).toJsonString({
+            clientId: props.stacApiClientId,
+            usePkceWithAuthorizationCodeGrant: true,
+          }),
 
         // customized settings
         ...props.apiEnv,