fix: omit 'Priority=' in the query URL

[favonia]

Description

Current, ListDNSRecords will generate an URL with Priority=. While it is mostly harmless, I prefer not to adjust my testing framework because of this, and here we are. The change follows the comment at a7b8640#r95126277.

Has your change been tested?

Yes, but using my own testing framework.

Types of changes

What sort of change does your code introduce/modify?

• 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.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.
• This change is using publicly documented (api.cloudflare.com or developers.cloudflare.com) and stable APIs.

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[favonia]

Already done in #1167. 😅