Unify Label parameter names to singular form in New-/Set-JiraIssue

[hmmwhatsthisdo]

Description

This PR aligns the naming convention for label parameters between New-JiraIssue and Set-JiraIssue.

Motivation and Context

Resolves #521.

New-JiraIssue takes -Labels, whereas Set-JiraIssue takes -Label. This PR updates both to be -Label with -Labels as an alias for backwards compatibility.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My code follows the code style of this project.
• I have added Pester Tests that describe what my changes should do.
• I have updated the documentation accordingly.

[lipkau]

Thank you for the PR.

My first impression is that -Labels (in plural) would be better, as one would expect a list.
Even the jql uses plural labels = api.

Do you agree?

[hmmwhatsthisdo]

Thank you for the PR.

My first impression is that -Labels (in plural) would be better, as one would expect a list. Even the jql uses plural labels = api.

Do you agree?

I went back and forth on this a bit. I agree that the Jira API uses the plural form and that, from the perspective of "we should match the behavior of the API", the plural form makes the most sense.

OTOH, PowerShell's development guidelines strongly recommend singular-noun parameter names, even for params that can take multivalued/array-type arguments. If you look at builtins like Add-LocalGroupMember, the -Member param also accepts multivalued data and is also the singular-noun form.

Looking at prior art within the module, -FixVersion is in a similar situation. The API uses fixVersions, whereas #103 added the singular noun -FixVersion with alias FixVersions.

I would posit that singular noun is best (as it's more closely aligned with best practices for the language) with [Alias()]es for the plural form in case users are expecting name alignment with the API.

[lipkau]

Agreed.
Do you mind creating an issue so we keep in mind to clean this up/get it consistent in all cases at some point?

[hmmwhatsthisdo]

Agreed. Do you mind creating an issue so we keep in mind to clean this up/get it consistent in all cases at some point?

Done: #523