add `documentPath` parameter to `webpage-screenshot` job processor

Controls where the screenshot Image _id value will be written

app/workers/media/job/webpage-screenshot.js

@@ -54,9 +54,13 @@ class WebpageScreenshotJob extends SiteWorkerProcess {
     await super.stop();
   }
 
+  /**
+   * Expected job data parameters: modelName, documentId, documentPath, pageUrl.
+   * @param {Job} job the Bull Queue job to be processed
+   */
   async processWebpageScreenshot (job) {
     const { image: imageService } = this.dtp.services;
-    const { modelName, documentId, pageUrl } = job.data;
+    const { modelName, documentId, documentPath, pageUrl } = job.data;
 
     const model = mongoose.model(modelName);
     if (!model) {
@@ -105,14 +109,9 @@ class WebpageScreenshotJob extends SiteWorkerProcess {
       job.data.screenshotImage = await imageService.create(job.data.semitism.author, imageDefinition, imageFile);
 
       this.jobLog(job, 'updating document with screenshot image');
-      await model.updateOne(
-        { _id: documentId },
-        {
-          $set: {
-            'attachments.screenshot': job.data.screenshotImage._id,
-          },
-        },
-      );
+      const updateOp = { $set: { } };
+      updateOp.$set[documentPath] = job.data.screenshotImage._id;
+      await model.updateOne({ _id: documentId }, updateOp);
 
       this.jobLog(job, 'screenshot captured and processed successfully');