refactor: Move Config-related code to internal/config

[t0mk]

This PR moves Config struct and related code to internal/config. It's part of breakdown of the refactor to internal/.

Part of #106

[t0mk]

This code is needed in Config for some user-agent magic, so I moved it to internal/fabric_utils

[displague]

Could you run goimports -w -l github.com/equinix/terraform-provider-equinix . on this branch.

The TF project imports should be in the group of non-native packages or a third group dedicated to local packages (which is what the above command will do).

[t0mk]

Could you run goimports -w -l github.com/equinix/terraform-provider-equinix . on this branch.

Done!

[displague]

Could we move internal to the root. While it has the same effect to use equinix/internal, in that we can freely change the go package signatures without worry of breaking third-party dependencies, the intent with this internal/ package will be to park everything there by default. This includes Equinix related code and generic (type juggling) or TF setup/helping code.

[codecov-commenter]

Codecov Report

Attention: 210 lines in your changes are missing coverage. Please review.

Comparison is base (26b2f3d) 60.11% compared to head (3d123b6) 59.46%.
Report is 48 commits behind head on main.

❗ Current head 3d123b6 differs from pull request most recent head 95578ce. Consider uploading reports for the commit 95578ce to get more accurate results

Files	Patch %	Lines
equinix/fabric_mapping_helper.go	0.00%	33 Missing ⚠️
equinix/resource_fabric_connection.go	0.00%	27 Missing ⚠️
equinix/resource_fabric_cloud_router.go	0.00%	15 Missing ⚠️
equinix/resource_fabric_service_profile.go	0.00%	12 Missing ⚠️
equinix/resource_fabric_routing_protocol.go	0.00%	11 Missing ⚠️
equinix/resource_ecx_l2_connection.go	0.00%	8 Missing ⚠️
equinix/resource_ecx_l2_serviceprofile.go	0.00%	8 Missing ⚠️
equinix/resource_network_acl_template.go	0.00%	8 Missing ⚠️
equinix/resource_network_device.go	0.00%	8 Missing ⚠️
equinix/resource_network_device_link.go	0.00%	8 Missing ⚠️
... and 23 more

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Additional details and impacted files

@@            Coverage Diff             @@
##             main     #459      +/-   ##
==========================================
- Coverage   60.11%   59.46%   -0.66%     
==========================================
  Files          99       98       -1     
  Lines       20045    19880     -165     
==========================================
- Hits        12051    11822     -229     
- Misses       7691     7764      +73     
+ Partials      303      294       -9     

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[displague]

the package name should avoid utils

Without looking at how this is used.. fabric/correlation ?

If this is only used in one or two files, especially for testing, I'd be tempted to make this a private helper adjacent to the code that needs it.

[t0mk]

There will be more fabric utils when we migrate further:

fabric_mapping_helper.go
fabric_mapping_service_profile_helper.go
fabric_port_mapping_helper.go

The CorrelationId code was in fabric_mapping_helper.go IIRC. I didn't think about it too much and moved it to fabric_utils originally. However it seems that CorrelationId is not used anywhere but in Config. So I moved it straight to Config.

[ocobles]

You can move that CorrelationId code into Config but I would create a helper folder under internal, you can add those mapping helpers you mention there and we will also need that also to avoid import cycles #406 (comment) so it should look like

[displague]

helper (like utils) is too generic of a name

• https://go.dev/blog/package-names#bad-package-names
• https://go.dev/doc/effective_go#names

[displague]

There were an unusually high number of E2E tests that failed in CI for this build, but none look to be related to this change