chore: Remove references to deprecated Modal.* components

[tassoevan]

Proposed changes (including videos or screenshots)

It replaces namespaced Modal.* components (e.g. Modal.Backdrop) with their named counterparts (ModalBackdrop).

Issue(s)

ARCH-1706

Steps to test or reproduce

Further comments

It looks like the @deprecated annotation is missing at the final types, and there is no document suggesting this as the way to go forward.

[dionisio-bot]

Looks like this PR is not ready to merge, because of the following issues:

• This PR is targeting the wrong base branch. It should target 7.9.0, but it targets 7.8.0

Please fix the issues and try again

If you have any trouble, please check the PR guidelines

[changeset-bot]

⚠️ No Changeset found

Latest commit: 97916f8

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[github-actions]

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[codecov]

Codecov Report

Attention: Patch coverage is 79.26421% with 62 lines in your changes missing coverage. Please review.

Project coverage is 65.36%. Comparing base (68426bd) to head (97916f8).
Report is 1 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #36396      +/-   ##
===========================================
+ Coverage    65.30%   65.36%   +0.05%     
===========================================
  Files         3156     3156              
  Lines       103992   104133     +141     
  Branches     19893    19900       +7     
===========================================
+ Hits         67915    68062     +147     
+ Misses       33398    33388      -10     
- Partials      2679     2683       +4     

Flag	Coverage Δ
e2e	58.39% <25.00%> (+<0.01%)	⬆️
unit	70.50% <79.46%> (+0.08%)	⬆️

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