Fix abi param encoding for tuple arrays

[ryanio]

Description

This PR fixes #3538 by handling param encoding of tuple arrays.

The first commit adds some failing tests (see ci failure), and the second commit should resolve them.

This was also a good opportunity to better organize some of the code by extracting formatParam into its own higher level method.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• I have selected the correct base branch.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• Any dependent changes have been merged and published in downstream modules.
• I ran npm run dtslint with success and extended the tests and types if necessary.
• I ran npm run test:unit with success.
• I ran npm run test:cov and my test cases cover all the lines and branches of the added code.
• I ran npm run build-all and tested the resulting files from dist folder in a browser.
• I have updated the CHANGELOG.md file in the root folder.
• I have tested my code on the live network.

[coveralls]

Coverage increased (+0.02%) to 89.638% when pulling 77f003e on issue/3538 into d43fd6d on 1.x.

[cgewecke]

Nice 🙂 LGTM.

[malaak-habashy]

@ryanio thank you