Update dnsapi script for OpenProvider switched current API specifications

[Lambiek12]

Updated the dnsapi script for OpenProvider to use their current REST APIs.

Main new feature it now allows the add/removal of single DNS record entry in a zone instead of having to-do a full zone overlay with all records when trying to add/remove a single entry.

Documentation for reference available at docs.openprovider.com.

Note;
Will have to update the documentation once approved, due to breaking change in API authentication. The hashed password isn't supported anymore by OpenProvider with the current (REST) API.

[Lambiek12]

Welcome First thing: don't send PR to the master branch, please send to the dev branch instead. Please make sure you've read our DNS API Dev Guide and DNS-API-Test. Then reply on this message, otherwise, your code will not be reviewed or merged. We look forward to reviewing your Pull request shortly ✨ 注意: 必须通过了 DNS-API-Test 才会被 review. 无论是修改, 还是新加的 dns api, 都必须确保通过这个测试.

Hopefully the DNS-API-Test is done correctly 🤞

Not very familiar with Github actions still using Azure DevOps on day-to-day tasks.

[Neilpang]

Is the old api still working ?

[Lambiek12]

Yes the old API is still online and the issue i run into early in the year where the script wasn't working, but this was fixed in the current master version this summer. Although i already started at the time to replace it with the newer REST API, finally decided to just do the PR to satisfy the request in #2104 thread to switch.

[Neilpang]

if the old api is still working, we MUST keep it compatible. otherwise the existing users would panic.
You can make a new one, eg: dns_openprovider_rest