Increase Content field size of gpg_key_import to MEDIUMTEXT (#22897)

Unfortunately #20896 does not completely prevent Data too long issues
and GPGKeyImport needs to be increased too.

Fix #22896

Signed-off-by: Andrew Thornton <art27@cantab.net>

models/migrations/v1_19/v242.go

@@ -0,0 +1,26 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package v1_19 //nolint
+
+import (
+	"code.gitea.io/gitea/modules/setting"
+
+	"xorm.io/xorm"
+)
+
+// AlterPublicGPGKeyImportContentFieldToMediumText: set GPGKeyImport Content field to MEDIUMTEXT
+func AlterPublicGPGKeyImportContentFieldToMediumText(x *xorm.Engine) error {
+	sess := x.NewSession()
+	defer sess.Close()
+	if err := sess.Begin(); err != nil {
+		return err
+	}
+
+	if setting.Database.UseMySQL {
+		if _, err := sess.Exec("ALTER TABLE `gpg_key_import` CHANGE `content` `content` MEDIUMTEXT"); err != nil {
+			return err
+		}
+	}
+	return sess.Commit()
+}