Addressing GOAWAY error on pagerduty_service_dependency

[imjaroiswebdev]

Closes #620

Following with the adoption of #507 workaround, I'm proceeding to remove the check for http error for retries, because it has been showing to be successful to mitigate the GOAWAY issues with the API.

Test results...

make testacc TESTARGS="-run TestAccPagerDutyBusinessServiceDependency"
==> Checking that code complies with gofmt requirements...
TF_ACC=1 go test $(go list ./... |grep -v 'vendor') -v -run TestAccPagerDutyBusinessServiceDependency -timeout 120m
?       github.com/terraform-providers/terraform-provider-pagerduty     [no test files]
=== RUN   TestAccPagerDutyBusinessServiceDependency_Basic
--- PASS: TestAccPagerDutyBusinessServiceDependency_Basic (15.56s)
PASS
ok      github.com/terraform-providers/terraform-provider-pagerduty/pagerduty   16.177s

[imjaroiswebdev]

Proceeding to immediately merge this as being a patch already applied to others resources facing the same issue, which is being progressively applied as the need arises.

[NargiT]

great ! I will integrate these changes monday and let you know ! Thank you

[NargiT]

no more issues since we upgraded ! 🎉 🎉 🎉 🎉 🍾 🍾 🍾 🍾

[imjaroiswebdev]

@NargiT thank you so much for letting know how it is going 🎉 💪🏽