IS migration client step is missing in the docs

Description:

In the migration, when we execute step 5(Upgrade the Identity component in WSO2 API Manager from version 5.7.0 to 5.10.0) of Upgrade API Manager to 3.2.0[1] part, we get the following error.

Caused by: java.lang.ClassNotFoundException: org.wso2.identity.apps.common.util.AppPortalConstants$AppPortal cannot be found by org.wso2.carbon.is.migration_1.0.142

This is due to a recently added change[2] in the IS migration client.

To avoid this we need to remove the following step from migration-config.yaml which is included under version: "5.10.0"

• name: "TenantPortalMigrator"
  order: 11

This step should be included in the docs.

[1] https://apim.docs.wso2.com/en/latest/install-and-setup/upgrading-wso2-api-manager/upgrading-from-260-to-320/#step-2-upgrade-api-manager-to-320

[2] https://github.com/wso2-extensions/identity-migration-resources/pull/172

Suggested Labels:

Affected Product Version:
APIM 3.2

Steps to reproduce:

Do a migration from APIM 2.6 to 3.2

Start with the linked “Upgrade API Manager to 3.2.0” documentation page and review the migration instructions for upgrading from APIM 2.6 to 3.2. Confirm how migration-config.yaml is described for version 5.10.0, then document removing the TenantPortalMigrator step (order 11); done means users are warned about this step and the ClassNotFoundException workaround.