[patch] add support for db2instance

[terc1997]

1. Description

Db2uCluster has been deprecated and it will require to migrate to Db2uInstance. The scenarios that this role need to cover:

• New installations should use Db2uInstance
• Re-installations, updates and upgrades with a previous deployed Db2uCluster should keep idempotency and not create a Db2uInstance replacing.

In the CLI, it needs to cover the update scenario.

2. Test Results

2.1. CLI Prompt

2.2. Tekton Pipeline

2.3. Unit Tests

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