Support multiple columns in column copy triggers

What does this MR do?

Relates to #326569 (closed)

In migration helpers we use "rename" triggers for certain migrations, whenever we need to ensure a destination column keeps the same value as a source column. We need to extend this functionality to support multiple source and destination columns, for migrations where we need to update more than one column at a time. At the same time, we need to maintain backwards compatibility with existing behavior to not break any existing migrations.

That means the install_rename_triggers and related functions should:

1. Create triggers with the same names, same behavior, and same syntax (to prevent diff in structure.sql)
2. Retain compatibility with their existing method signature, while also supporting arrays of column names

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