fix: record missing when record count greater than 20

[EkkoG]

According to the doc https://api.cloudflare.com/#dns-records-for-a-zone-list-dns-records

API only returns 1 page, and 20 records per page, so when record count greater than 20, some record will missing in local cache, then RecordNotFound occur. This patch changes the page size to 100, the max page size, to avoid the issue.

[undefinedplayer]

Thanks for the PR. It'll be great to expose per_page as an parameter upstream to the main function and set it default to 100? In that case it would support the case if it has more than 100 records.