FireStore: Make Changes to Lookup Tables without Source Control

I want to seed a Firestore Database containing a lookup table. We are using Java 8 with Github/Intellij.
We are thinking of using this example https://stackoverflow.com/questions/63004211/how-do-i-seed-data-to-firebase-firestore to seed/update lookup table data every calendar quarter.

Is there any way to seed/update data in Firestore using Java (or any other coding language), while avoiding making changes to Git source control? What is google's recommended way? Changes need to be made automatically across Devops environments, Dev, QA, Staging, Production.
Changes need to be able to change by ProductOwners team in UI, without using code if possible.

https://firebase.google.com/docs/firestore/manage-data/add-data#java

{
	id: 1,
	productName: 'Book',
	description: 'reading books',

	id: 2,
	productName: 'Car',
	description: 'automobile cars used for driving',

	id: 3,
	productName: 'Television',
	description: 'Screen used for watching items',

    etc..
}

1. Add the seed data to a Firestore collection where the stakeholders have read/write permission
2. Create a Cloud Function triggered by Firestore onWrite events that propagates the given change to the targeted locations

The example at the above-linked documentation shows how to create a Cloud Function in NodeJS using the Firebase Admin SDK. For Java you can use this example from the Firestore documentation:

import com.google.cloud.functions.Context;
import com.google.cloud.functions.RawBackgroundFunction;
import com.google.gson.Gson;
import com.google.gson.JsonObject;
import java.util.logging.Logger;

public class FirebaseFirestore implements RawBackgroundFunction {
  private static final Logger logger = Logger.getLogger(FirebaseFirestore.class.getName());

  // Use GSON (https://github.com/google/gson) to parse JSON content.
  private static final Gson gson = new Gson();

  @Override
  public void accept(String json, Context context) {
    JsonObject body = gson.fromJson(json, JsonObject.class);
    logger.info("Function triggered by event on: " + context.resource());
    logger.info("Event type: " + context.eventType());

    if (body != null && body.has("oldValue")) {
      logger.info("Old value:");
      logger.info(body.get("oldValue").getAsString());
    }

    if (body != null && body.has("value")) {
      logger.info("New value:");
      logger.info(body.get("value").getAsString());
    }
  }
}

Alternatively you can use CloudEvent triggers for Gen 2 Cloud Functions:

package mycloudeventfunction;

import com.google.cloud.functions.CloudEventsFunction;
import io.cloudevents.CloudEvent;

// Define a class that implements the CloudEventsFunction interface
public class MyCloudEventFunction implements CloudEventsFunction {
  // Implement the accept() method to handle CloudEvents
  @Override
  public void accept(CloudEvent event) {
    // Your code here
    // Access the CloudEvent data payload via event.getData()
    // To get the data payload as a JSON string, use:
    // new String(event.getData().toBytes())
  }
}

You would need to adapt this example to use the appropriate EventArc trigger for Cloud Firestore by parsing the JSON format for CloudEvents. Unfortunately there don't appear to be any direct examples of this in Google's documentation as Gen 2 functions are still relatively new.