fix(forms): disable radio inputs in template driven forms - #20310

In template driven forms, disable radio controls when they are initially disabled using data binding.

closes #18206

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/angular/angular/blob/master/CONTRIBUTING.md#commit
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[X] Bugfix
[ ] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Documentation content changes
[ ] angular.io application / infrastructure changes
[ ] Other... Please describe:

What is the current behavior?

#18206

Issue Number: 18206

What is the new behavior?

In template driven forms, the radio inputs are correctly disabled when they are initially disabled using data binding.

Does this PR introduce a breaking change?

[ ] Yes
[X] No

Other information