[Docs][3.3] Update documentation for Row Tracking to include Row Tracking Backfill introduced in Delta 3.3 (#4014)

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## Description
- Cherry-pick #3968 into Delta
3.3.
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Author: longvu-db

docs/source/delta-row-tracking.md

@@ -11,7 +11,7 @@ Row tracking allows <Delta> to track row-level lineage in a <Delta> table. When
 
 - **Row commit versions** record the last version of the table in which the row was modified. A row is assigned a new version whenever it is modified using a `MERGE` or `UPDATE` statement.
 
-.. note:: This feature is available in <Delta> 3.2.0 and above. This feature is in experimental support mode with [_](#limitations).
+.. note:: This feature is available in <Delta> 3.2.0 and above. Enabling this feature on existing non-empty tables is available in <Delta> 3.3.0 and above.
 
 ## Enable row tracking
 
@@ -37,7 +37,7 @@ You must explicitly enable row tracking using one of the following methods:
   CREATE TABLE graduate CLONE student;
   ```
 
-- **Existing table**: Set the table property `'delta.enableRowTracking' = 'true'` in the `ALTER TABLE` command.
+- **Existing table**: Available from Delta 3.3 and above, set the table property `'delta.enableRowTracking' = 'true'` in the `ALTER TABLE` command.
 
   ```sql
   ALTER TABLE grade SET TBLPROPERTIES ('delta.enableRowTracking' = 'true');
@@ -108,7 +108,6 @@ ALTER TABLE table_name SET TBLPROPERTIES (delta.enableRowTracking = false);
 The following limitations exist:
 
 - The row ids and row commit versions metadata fields cannot be accessed while reading the [Change data feed](/delta/delta-change-data-feed.md).
-- Row Tracking can currently only be enabled when creating the table or when the table is empty. Enabling row tracking on a non-empty table is currently not supported.
 - Once the Row Tracking feature is added to the table it cannot be removed without recreating the table.
 
 .. <Delta> replace:: Delta Lake