Add missing error messages to onboarding form

[Nateowami]

Somehow I forgot to put error messages on two of the form fields.

Before

After

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This change is 

[devin-ai-integration]

✅ Devin Review: No Issues Found

Devin Review analyzed this PR and found no bugs or issues to report.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 81.26%. Comparing base (9f24d06) to head (663142e).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #3831   +/-   ##
=======================================
  Coverage   81.26%   81.26%           
=======================================
  Files         625      625           
  Lines       39638    39638           
  Branches     6443     6419   -24     
=======================================
  Hits        32213    32213           
- Misses       6416     6429   +13     
+ Partials     1009      996   -13     

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[RaymondLuong3]

@RaymondLuong3 reviewed 2 files and all commit messages, and made 1 comment.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on Nateowami).

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src/SIL.XForge.Scripture/ClientApp/src/app/translate/draft-generation/draft-signup-form/draft-onboarding-form.component.html line 73 at r1 (raw file):

                />
                @if (signupForm.controls.translationLanguageName.hasError("required")) {
                  <mat-error>{{ t("translation_language_name_required") }}</mat-error>

Is there a reason this needs to be specific. I would think it is better to just say "this field is required" since that translation is easy and shouldn't need to be updated.

Code quote:

<mat-error>{{ t("translation_language_name_required") }}</mat-error>