fix: upgrade hcloud-go to v2

[jooola]

Attempt to migrate the hcloud-go library to v2, to be able to finally drop the v1 version.

We previously discussed of not going this route, but the effort of porting new features in both hcloud-go versions is bigger than upgrade the library in the terrafrom plugin.

If this change ends up being impossible to test and too dangerous, we will just continue the route we initially choose: migrating for to the plugin framework then the hcloud-go library.

Fix #877

[codecov]

Codecov Report

Attention: Patch coverage is 91.10169% with 21 lines in your changes missing coverage. Please review.

Project coverage is 66.39%. Comparing base (a90209c) to head (3f36288).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
internal/util/sdk.go	47.05%	8 Missing and 1 partial ⚠️
hcloud/plugin_provider.go	0.00%	2 Missing ⚠️
internal/loadbalancer/resource_target.go	81.81%	2 Missing ⚠️
internal/primaryip/resource.go	84.61%	2 Missing ⚠️
internal/util/id.go	83.33%	2 Missing ⚠️
hcloud/provider.go	50.00%	1 Missing ⚠️
internal/firewall/resource.go	83.33%	1 Missing ⚠️
internal/floatingip/resource.go	85.71%	1 Missing ⚠️
internal/network/resource_subnet.go	75.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1062      +/-   ##
==========================================
- Coverage   66.53%   66.39%   -0.14%     
==========================================
  Files          67       69       +2     
  Lines        9947     9916      -31     
==========================================
- Hits         6618     6584      -34     
- Misses       2614     2618       +4     
+ Partials      715      714       -1     

Flag	Coverage Δ
e2e	66.39% <91.10%> (-0.14%)	⬇️
unit	30.84% <9.74%> (+0.25%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.