feat: allow setting contentEncoding during compose

[zuozp8]

Fixes #2430

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[ddelgrosso1]

Thanks for the contribution @zuozp8. It looks like the test

Bucket
       combine
         should make correct API request:

needs to be updated.

[zuozp8]

@ddelgrosso1 sure, I updated the test

I made sure my undefined doesn't look and caused content-type to be undefined too in that test

[zuozp8]

@ddelgrosso1 linter wants to change files that I didn't touch, should i change them?

wouldn't it be better to commit package-lock.json into repo to avoid unexpected version bumps?

[ddelgrosso1]

@zuozp8 don't worry about them, I have another PR open that will fix them. As a general rule, we don't normally commit package locks but sometimes this is the outcome 😆

[ddelgrosso1]

Thanks again for the contribution @zuozp8. I will get this merged / released after Cloud Next is over.