[patch] improve checks for installing AI Service 9.2 tenant operator

[boonware]

Issue

MASAIB-1994

Description

• When the channel is not 9.1 we currently install the new AI Service namespace-scoped tenant operator. This will cause a failure if the current feature channel release is installed since the catalog does not yet contain a feature channel release of this operator. To solve this we use the "aiservice_migration" role to perform a check which determines if the new operator is needed or not, and only attempt to install the operator if true. This facilitates current test efforts for the upcoming 9.2 release.
• Ensure the AI Service migration role automatically sets the same channel for the ibm-aiservice-tenant subscription based on the subscription for ibm-aiservice, with an allowed override for dev purposes.

Test Results

• Verified by installing the 9.2.x-feature channel and confirming that resources were installed to correct namespaces and that the 9.2 tenant operator was not installed.
• Also tested as part of [minor] Invoke AI Service migration from update pipeline cli#2171

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