fix(modal): the width of the modal box can be displayed in the center as the browser window size changes

[James-9696]

… browser window size changes

PR

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our Commit Message Guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• CI related changes
• Documentation content changes
• Other... Please describe:

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Does this PR introduce a breaking change?

• Yes
• No

Other information

[github-actions]

[e2e-test-warn]
The component to be tested is missing.

The title of the Pull request should look like "fix(vue-renderless): [action-menu, alert] fix xxx bug".

Please make sure you've read our contributing guide