Removed "required" tag from failOnValidationErrors

[venera-program]

What this PR does / why we need it:
Using the "required" tag on the DataInputSchema.FailOnValidationErrors field operates counter-intuitively to the go-playground docs. This also causes workflows to fail validation when the value of the field is manually set to false because the validator interprets this as the default/unset value.

Special notes for reviewers:
Not sure where to add a test for this case, need some insight on that front.

Additional information (if needed):
Go-playground doc reference: https://pkg.go.dev/github.com/go-playground/validator/v10#hdr-Required

This validates that the value is not the data types default zero value. For numbers ensures value is not zero. For strings ensures value is not "". For slices, maps, pointers, interfaces, channels and functions ensures the value is not nil. For structs ensures value is not the zero value when using WithRequiredStructEnabled.

[ricardozanini]

Either we remove the required tag or keep this field as a pointer, so nil would be considered empty. Now the default will be false. That's fine. :)

[spolti]

+1 to keep as required and use pointer.

[ribeiromiranda]

@ricardozanini I agree to only removing the required tag, it is initialized by ApplyDefault, initially it is true and the other possibility is false. I think, it doesn't need to be a pointer.

func (d *DataInputSchema) ApplyDefault() {
	d.FailOnValidationErrors = true
}

@venera-program You can add a test in https://github.com/serverlessworkflow/sdk-go/blob/main/model/workflow_validator_test.go

[ricardozanini]

@venera-program let's keep it as it is to simplify things rather than a pointer and please add a test case where @ribeiromiranda pointed out. 🙏

[venera-program]

@ricardozanini I added a test that fails with the scenario caused by the old tag and a test parsing from a yaml source.

Edit: PR is done from my end.

[ricardozanini]

@ribeiromiranda can u review?

[ribeiromiranda]

@ribeiromiranda can u review?

Review completed.

[ricardozanini]

@venera-program let me know if you need a patch release or if there's more to add before we do a release.