Add support for configuring a PR's autoCompleteIgnoreConfigIds

**Is your feature request related to a problem? Please describe.**
There is currently no way to configure a PR's `completionOptions.autoCompleteIgnoreConfigIds` at creation or afterwards.
This causes issues when creating an auto completing PR against a branch with the [linked work item policy](https://docs.microsoft.com/en-us/azure/devops/repos/git/branch-policies?view=azure-devops&tabs=browser#check-for-linked-work-items) configured as optional, since the policy defaults to blocking the autocomplete.

**Describe the solution you'd like**
Please add a new parameter, `--auto-complete-ignore-ids`, to both `az repos pr create` and `az repos pr update`.
This seems to be the existing pattern as all the other [GitPullRequestCompletionOptions](https://docs.microsoft.com/en-us/rest/api/azure/devops/git/pull-requests/create?view=azure-devops-rest-6.0#gitpullrequestcompletionoptions), with the exception of `mergeStrategy`, are included at the top level.

**Additional context**
See also this request to add the `mergeStrategy` completion option:
Azure/azure-cli-extensions#1721