Define IDL instructions for the interest bearing mint extension

[lorisleiva]

The instructions of the interest bearing mint extension still need to be defined in the idl.json file for them to be generated in the various clients.

The issue is a request to perform the following actions:

• Add all the instructions of the interest bearing mint extension in the idl.json file. See how the program defines them to access that information.
• Run pnpm generate.
• Add at least one test for all instructions in the extensions by following the same structure as the existing tests of the other extensions.
• When applicable, add the initialize or enable instruction of the extension in the getInitializeInstructionsForExtensions.ts helpers.

Here are some related PRs to get some inspiration from:

• Confidential transfer (Mint and token extension)
• Default account state (Mint extension)
• Metadata Pointer (Mint extension)
• Memo transfer (Token extension)