TCE-1655: Retry failed GET organization and project requests

[itsjaspermilan]

🛠️ Description

From time to time, the GET requests for fetching the organization and project will return a 502 or 504 which can cause E2E pipelines to fail. This PR addresses the issue by adding in some retry logic so if the 502s or 504s are temporary, we don't have to stop the whole pipeline in order to retry.

🚢 Release Note

Release note for CHANGELOG:

* all: Add retry logic to the get organization and get project endpoints [GH-nnnn]

🏗️ Acceptance tests

• Are there any feature flags that are required to use this functionality?
• Have you added an acceptance test for the functionality being added?
• Have you run the acceptance tests on this branch?

Output from acceptance testing:

$ make testacc TESTARGS='-run=TestShouldRetryErrorCode'
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test ./internal/... -v -run=TestShouldRetryErrorCode -timeout 210m
?       github.com/hashicorp/terraform-provider-hcp/internal/clients    [no test files]
testing: warning: no tests to run
PASS
ok      github.com/hashicorp/terraform-provider-hcp/internal/consul     0.223s [no tests to run]
testing: warning: no tests to run
PASS
ok      github.com/hashicorp/terraform-provider-hcp/internal/input      0.143s [no tests to run]
=== RUN   TestShouldRetryErrorCode
--- PASS: TestShouldRetryErrorCode (0.00s)
PASS
ok      github.com/hashicorp/terraform-provider-hcp/internal/provider   0.314s
...

[bcmdarroch]

Logic looks good!

One suggestion for code organization: these helpers might make more sense living under the clients package: https://github.com/hashicorp/terraform-provider-hcp/tree/main/internal/clients