Increase `max_operation_data_length` Constant

Context

Increase max_operation_size constant of the protocol from 16KB to 32KB. This has the effect of slightly more than doubling the maximum size of a smart contract, but also allows for larger operations in general.

A detailed rationale for this change is provided here: https://forum.tezosagora.org/t/increase-operation-size-limit/2593

Manually testing the MR

I tested this operation manually by:

• Building a smart contract operation that was over 16KB in size
• Injecting a contract origination operation to rpctest.tzbeta.net (Tezos Foundation's Delphinet Nodes) and verifying that I received node.prevalidation.oversized_operation
• Building a flextesa sandbox locally (following this guide and injecting the same origination operation, verifying it was able to succeed.

Describe how reviewers and approvers can test this MR.

Checklist

• Document the interface of any function added or modified (see the coding guidelines)
• Provide automatic testing (see the testing guide).
• Add item in the Development Version section of CHANGES.md (only for new features and bug fixes).