fix(workflows)!: updated how empty fields are handled on create

[usfdmiller]

This is a breaking change. I'm unabashedly copying the changes made to AiWorkflowsUpdateWorkflowInput in pull request #937 and applying them to AiWorkflowsCreateWorkflowInput. I'm hoping this aligns workflow behavior between creates and updates around empty fields and JSON marshaling. I'd really like to create workflows in a disabled state and this is one of the last little issues preventing me from upgrading to the 3.0+ provider. I even created issue #932 a while back regarding this problem.

This is pushing my novice GO knowledge, so please let me know if I've made a questionable change, I'm not meeting standards, or if I've left out information.

Thanks!

[CLAassistant]

All committers have signed the CLA.

[mbazhlekova]

@usfdmiller Thank you for your contribution! Sorry for the delay on this. We're doing some feature work that we're hoping to get into v2 before releasing another major version since it's a bit of a hassle in Go. Happy to review once that work is finished.

[usfdmiller]

It looks like my core issue here, being unable to create workflows in a disabled state, was resolved in PR #959. That said, I'm going to close this PR. Thanks!