fix: username not changing when editing incoming webhook

[dieselftw]

Proposed changes (including videos or screenshots)

Currently, changing the "Post as" field while editing incoming webhooks does not change the value. This PR aims to resolve the same.

Before:

https://github.com/RocketChat/Rocket.Chat/assets/98163873/2d15c156-5c46-428b-b3a4-40d54b4e19ef

After:

https://github.com/RocketChat/Rocket.Chat/assets/98163873/1cc4d02d-9a78-47c9-95a7-0ed69b849b0c

Issue(s)

fixes #31425

Steps to test or reproduce

1. Open an existing webhook integration
2. Change the contents of the Post as field
3. Save it

Further comments

[changeset-bot[bot]]

⚠️ No Changeset found

Latest commit: f9a40721839d3589c9fd41d04e77bfc37f2220da

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (cb9c6ba) 54.33% compared to head (f9a4072) 54.31%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #31442      +/-   ##
===========================================
- Coverage    54.33%   54.31%   -0.02%     
===========================================
  Files         2276     2269       -7     
  Lines        50124    50040      -84     
  Branches     10220    10358     +138     
===========================================
- Hits         27233    27179      -54     
+ Misses       20406    20375      -31     
- Partials      2485     2486       +1     

Flag	Coverage Δ
e2e	53.13% <ø> (-0.04%)	:arrow_down:
e2e-api	39.88% <ø> (+0.05%)	:arrow_up:
unit	76.47% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

[dieselftw]

@gabriellsh @hugocostadev can I get a review on this? I feel like it's an important fix. Thanks! :)

[dieselftw]

@juliajforesti is there a problem with this fix? I'd appreciate some feedback! Thanks :)