Update contract class to not mutate options object

[spacesailor24]

closes #5304

[render]

Your Render PR Server URL is https://web3-js-pr-5394.onrender.com.

Follow its progress at https://dashboard.render.com/static/srv-cc6okipgp3jv8lhb7k8g.

[coveralls]

Pull Request Test Coverage Report for Build 2953468494

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 15 unchanged lines in 3 files lost coverage.
• Overall coverage decreased (-0.07%) to 74.575%

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Files with Coverage Reduction	New Missed Lines	%
packages/web3-core-helpers/lib/errors.js	1	80.88%
packages/web3-providers-ws/lib/index.js	3	91.81%
packages/web3-eth-contract/lib/index.js	11	91.96%

Totals
Change from base Build 2924335251:	-0.07%
Covered Lines:	3272
Relevant Lines:	4136

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💛 - Coveralls

[nikoulai]

Nice! The PR solves the problem, but, should this be happening? Is it behavior we want?

[spacesailor24]

Nice! The PR solves the problem, but, should this be happening? Is it behavior we want?

@nikoulai

From my understanding, you should never mutate arguments given to a function (unless that's what the function is specifically designed to do), you should always return the data and let the function caller decide what to do it with it. In the case of _getOrSetDefaultOptions, I think you could argue that mutating the options objects was be design, but it leads to frustrating behavior for the user that isn't straightforward to debug (as mentioned by the user whom opened the issue), so I see this as an improvement for the library whether or not it's actually a bug