(core) Rename popup for group by columns

Summary:
Showing rename popup on group by column with disabled label section. It only allows to set description.

Unrelated:
- Fixing HostedMetadataManager test

Test Plan: Updated tests

Reviewers: Spoffy

Reviewed By: Spoffy

Subscribers: Spoffy

Differential Revision: https://phab.getgrist.com/D4371

app/server/lib/HostedStorageManager.ts

@@ -151,7 +151,7 @@ export class HostedStorageManager implements IDocStorageManager {
     if (!externalStoreDoc) { this._disableS3 = true; }
     const secondsBeforePush = options.secondsBeforePush;
     if (options.pushDocUpdateTimes) {
-      this._metadataManager = new HostedMetadataManager(callbacks.setDocsMetadata);
+      this._metadataManager = new HostedMetadataManager(callbacks.setDocsMetadata.bind(callbacks));
     }
     this._uploads = new KeyedOps(key => this._pushToS3(key), {
       delayBeforeOperationMs: secondsBeforePush * 1000,