fix: clear content should not be set empty object

[ybzky]

等0.6.7之后再合入

Pull Request Checklist

• Related tickets or issues have been linked in the PR description (or missing issue).
• Naming convention is followed (do please check it especially when you created new plugins, commands and resources).
• Unit tests have been added for the changes (if applicable).
• Breaking changes have been documented (or no breaking changes introduced in this PR).

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Playwright test results

 25 passed

Details

 25 tests across 12 suites
 6 minutes, 6 seconds
 3e21b07
 For more information, see full report

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 34.12%. Comparing base (f1cbe91) to head (3e21b07).
Report is 1 commits behind head on dev.

Additional details and impacted files

@@           Coverage Diff           @@
##              dev    #4861   +/-   ##
=======================================
  Coverage   34.11%   34.12%           
=======================================
  Files        2627     2627           
  Lines      137014   137070   +56     
  Branches    30418    30431   +13     
=======================================
+ Hits        46742    46774   +32     
- Misses      90272    90296   +24     

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[univer-bot]

Bot detected the issue body's language is not English, translate it automatically. 👯👭🏻🧑‍🤝‍🧑👫🧑🏿‍🤝‍🧑🏻👩🏾‍🤝‍👨🏿👬🏿

Origin Title: fix: clear content should not be set empty object

Title: fix: clear content should not be set empty object

---

等0.6.7之后再合入

Pull Request Checklist

• Related tickets or issues have been linked in the PR description (or missing issue).
• Naming convention is followed (do please check it especially when you created new plugins, commands and resources).
• Unit tests have been added for the changes (if applicable).
• Breaking changes have been documented (or no breaking changes introduced in this PR).