[TF-33692] Add SpeculativeEnabled in create/update options for a Stack

[arunatibm]

Description

This is a prerequisite change to be made so that the terraform-provider-tfe can also add the Speculative Enabled processing and allow us to support setting speculative_enabled in the stack model. This PR is required by hashicorp/terraform-provider-tfe#1963.

The ticket https://hashicorp.atlassian.net/browse/TF-33626 is to allow setting of this property in the stack and the gotfe` update is required first.

Testing plan

Will be tested using the integration tests and then again with the terraform-provider-tfe PR hashicorp/terraform-provider-tfe#1963.

External links

JIRA Ticket

Output from tests

Including output from tests may require access to a TFE instance. Ignore this section if you have no environment to test against.

TestStackCreateAndList

$ go test ./... -v -run TestStackCreateAndList
=== RUN   TestStackCreateAndList
=== PAUSE TestStackCreateAndList
=== CONT  TestStackCreateAndList
=== RUN   TestStackCreateAndList/List_without_options
=== PAUSE TestStackCreateAndList/List_without_options
=== RUN   TestStackCreateAndList/List_with_project_filter
=== PAUSE TestStackCreateAndList/List_with_project_filter
=== RUN   TestStackCreateAndList/List_with_name_filter
=== PAUSE TestStackCreateAndList/List_with_name_filter
=== RUN   TestStackCreateAndList/List_with_sort_options
=== PAUSE TestStackCreateAndList/List_with_sort_options
=== RUN   TestStackCreateAndList/List_with_pagination
=== PAUSE TestStackCreateAndList/List_with_pagination
=== CONT  TestStackCreateAndList/List_without_options
=== CONT  TestStackCreateAndList/List_with_sort_options
=== CONT  TestStackCreateAndList/List_with_pagination
=== CONT  TestStackCreateAndList/List_with_name_filter
=== CONT  TestStackCreateAndList/List_with_project_filter
--- PASS: TestStackCreateAndList (5.13s)
    --- PASS: TestStackCreateAndList/List_with_pagination (0.31s)
    --- PASS: TestStackCreateAndList/List_with_name_filter (0.39s)
    --- PASS: TestStackCreateAndList/List_without_options (0.41s)
    --- PASS: TestStackCreateAndList/List_with_project_filter (0.44s)
    --- PASS: TestStackCreateAndList/List_with_sort_options (0.57s)
PASS
ok  	github.com/hashicorp/go-tfe	6.584s
?   	github.com/hashicorp/go-tfe/examples/backing_data	[no test files]
?   	github.com/hashicorp/go-tfe/examples/configuration_versions	[no test files]
?   	github.com/hashicorp/go-tfe/examples/organizations	[no test files]
?   	github.com/hashicorp/go-tfe/examples/projects	[no test files]
?   	github.com/hashicorp/go-tfe/examples/registry_modules	[no test files]
?   	github.com/hashicorp/go-tfe/examples/run_errors	[no test files]
?   	github.com/hashicorp/go-tfe/examples/state_versions	[no test files]
?   	github.com/hashicorp/go-tfe/examples/users	[no test files]
?   	github.com/hashicorp/go-tfe/examples/workspaces	[no test files]
?   	github.com/hashicorp/go-tfe/mocks	[no test files]

TestStackReadUpdateDelete

$ go test ./... -v -run TestStackReadUpdateDelete
=== RUN   TestStackReadUpdateDelete
=== PAUSE TestStackReadUpdateDelete
=== CONT  TestStackReadUpdateDelete
--- PASS: TestStackReadUpdateDelete (8.98s)
PASS
ok  	github.com/hashicorp/go-tfe	9.867s
?   	github.com/hashicorp/go-tfe/examples/backing_data	[no test files]
?   	github.com/hashicorp/go-tfe/examples/configuration_versions	[no test files]
?   	github.com/hashicorp/go-tfe/examples/organizations	[no test files]
?   	github.com/hashicorp/go-tfe/examples/projects	[no test files]
?   	github.com/hashicorp/go-tfe/examples/registry_modules	[no test files]
?   	github.com/hashicorp/go-tfe/examples/run_errors	[no test files]
?   	github.com/hashicorp/go-tfe/examples/state_versions	[no test files]
?   	github.com/hashicorp/go-tfe/examples/users	[no test files]
?   	github.com/hashicorp/go-tfe/examples/workspaces	[no test files]
?   	github.com/hashicorp/go-tfe/mocks	[no test files]

Rollback Plan

N/A

Changes to Security Controls

N/A

[hashicorp-cla-app]

All committers have signed the CLA.

[github-actions]

Reminder to the contributor that merged this PR: if your changes have added important functionality or fixed a relevant bug, open a follow-up PR to update CHANGELOG.md with a note on your changes.