change erratum synopsis from CharField(255) to TextField

EPEL 10.1 has errata with synopsis text exceeding 255 characters,
causing psycopg2.errors.StringDataRightTruncation crash in
get_or_create_erratum(). TextField removes the length constraint.

Author: furlongm

errata/migrations/0010_synopsis_textfield.py

@@ -0,0 +1,18 @@
+# Generated by Django 4.2.28 on 2026-05-02 03:49
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('errata', '0009_backfill_cached_counts'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='erratum',
+            name='synopsis',
+            field=models.TextField(),
+        ),
+    ]

errata/models.py

@@ -33,7 +33,7 @@ class Erratum(models.Model):
     name = models.CharField(max_length=255, unique=True)
     e_type = models.CharField(max_length=255)
     issue_date = models.DateTimeField()
-    synopsis = models.CharField(max_length=255)
+    synopsis = models.TextField()
     affected_packages = models.ManyToManyField(Package, blank=True, related_name='affected_by_erratum')
     fixed_packages = models.ManyToManyField(Package, blank=True, related_name='provides_fix_in_erratum')
     from operatingsystems.models import OSRelease