fix: duplicate scroller issue in post edit page

[LIlGG]

What type of PR is this?

/kind bug
/area editor
/milestone 2.14.x

What this PR does / why we need it:

在默认富文本编辑器下，当滚动时有概率会使页面小于正常大小。在文章最底部使用 AI 插件更加容易复现。

How to test it?

测试文章滚动时是否会小于正常大小，推荐在文章最底部使用 AI 插件来复现和测试。

Which issue(s) this PR fixes:

Fixes #3853

Does this PR introduce a user-facing change?

修复文章编辑页面出现多个滚动条导致的页面高度样式问题。

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.4% Duplication on New Code

See analysis details on SonarCloud

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 56.56%. Comparing base (5fdf6c0) to head (abae729).
Report is 72 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #5537      +/-   ##
============================================
- Coverage     56.91%   56.56%   -0.35%     
+ Complexity     3319     3310       -9     
============================================
  Files           587      592       +5     
  Lines         18968    19178     +210     
  Branches       1401     1355      -46     
============================================
+ Hits          10795    10848      +53     
- Misses         7594     7769     +175     
+ Partials        579      561      -18     

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[guqing]

/lgtm

[ruibaby]

/lgtm

[f2c-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: ruibaby

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• ui/OWNERS [ruibaby]

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