docs(upgrade): fix migration numbers and the redundant migrate_cwe step (F10)

- Update the migration list to the renumbered chain (0280-0284).
- Remove the contradiction: 0284_backfill_finding_cwe already backfills every
  existing finding automatically, so migrate_cwe is NOT a required upgrade
  step (it would repeat that work). Reframe migrate_cwe as an optional,
  idempotent re-scan for later use (e.g. after a parser CWE change).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: Maffooch

docs/content/releases/os_upgrading/3.2.md

@@ -37,22 +37,23 @@ finding's CWE field, plus any additional CWEs a parser supplies). The finding ex
 
 Five migrations run automatically on upgrade:
 
-- `0276_vulnerability_id_type` — adds the indexed `vulnerability_id_type` column and a leading
+- `0280_vulnerability_id_type` — adds the indexed `vulnerability_id_type` column and a leading
   index on `vulnerability_id`.
-- `0277_backfill_vulnerability_id_type` — backfills `vulnerability_id_type` and removes duplicate
+- `0281_backfill_vulnerability_id_type` — backfills `vulnerability_id_type` and removes duplicate
   `(finding, vulnerability_id)` rows (keeping the earliest).
-- `0278_unique_finding_vulnerability_id` — adds the unique constraint on `(finding, vulnerability_id)`.
-- `0279_finding_cwe` — creates the `Finding_CWE` table (unique per `(finding, cwe)`).
-- `0280_backfill_finding_cwe` — seeds `Finding_CWE` rows from the legacy `Finding.cwe` values.
+- `0282_unique_finding_vulnerability_id` — adds the unique constraint on `(finding, vulnerability_id)`.
+- `0283_finding_cwe` — creates the `Finding_CWE` table (unique per `(finding, cwe)`).
+- `0284_backfill_finding_cwe` — seeds `Finding_CWE` rows for all existing findings from their
+  legacy `Finding.cwe` values.
 
 ### What you need to do
 
-The migrations are applied automatically. New and edited findings populate their CWE relationship
-automatically. To backfill `Finding_CWE` rows for **existing** findings, run the idempotent command
-after upgrading:
+Nothing — the migrations are applied automatically, `0284_backfill_finding_cwe` backfills every
+existing finding, and new/edited findings populate their CWE relationship on save and import.
 
-```
-manage.py migrate_cwe
-```
+The `manage.py migrate_cwe` management command is **optional** and is *not* required on upgrade
+(it would repeat the work `0284` already did). It exists only as an idempotent re-scan you can run
+later — for example after a parser upgrade changes how a scan's CWEs are derived — to reconcile
+`Finding_CWE` rows from the current `Finding.cwe` values.
 
 For more information, check the [Release Notes](https://github.com/DefectDojo/django-DefectDojo/releases/tag/3.2.0).