Fix deprecated String.substr, use String.substring instead.

[dumganhar]

The signature '(from: number, length?: number | undefined): string' of 'labelString.substr' is deprecated.ts(6387)
lib.es5.d.ts(522, 8): The declaration was marked as deprecated here.
(method) String.substr(from: number, length?: number): string
Gets a substring beginning at the specified location and having the specified length.

@deprecated — A legacy feature for browser compatibility

@param from — The starting position of the desired substring. The index of the first character in the string is zero.

@param length — The number of characters to include in the returned substring.

Changelog

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Continuous Integration

This pull request:

• needs automatic test cases check.

  Manual trigger with @cocos-robot run test cases afterward.

• does not change any runtime related code or build configuration

  If any reviewer thinks the CI checks are needed, please uncheck this option, then close and reopen the issue.

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Compatibility Check

This pull request:

• changes public API, and have ensured backward compatibility with deprecated features.
• affects platform compatibility, e.g. system version, browser version, platform sdk version, platform toolchain, language version, hardware compatibility etc.
• affects file structure of the build package or build configuration which requires user project upgrade.
• introduces breaking changes, please list all changes, affected features and the scope of violation.

[github-actions]

⚠️ Package size ⤴ 36 bytes, old: 5225108, new: 5225144

Interface Check Report

This pull request does not change any public interfaces !

[dumganhar]

@cocos-robot run test cases

[github-actions]

@dumganhar, Please check the result of run test cases:

• Test Platform: PR-Test
• Editor Version: v3.8.6
• Task Result: FAIL
• Task URL: https://cctest.cocos.org/#/reportview/PR-TEST/bff0bb0d-96bf-4003-b475-6358d9b7a4ea/-1
• GitHub Action: https://github.com/cocos/cocos-engine/actions/runs/13152050512

Task Details

Platform	build	boot	runned	crashScene	FailScene
web-mobile	PASS	PASS	FAIL		graphics-line-join
ios	PASS	PASS	PASS
mac	PASS	PASS	PASS

[github-actions]

@dumganhar, Please check the result of run test cases:

• Test Platform: PR-Test
• Editor Version: v3.8.6
• Task Result: FAIL
• Task URL: https://cctest.cocos.org/#/reportview/PR-TEST/1921649b-ac12-4d00-b692-20de29b8e67a/-1
• GitHub Action: https://github.com/cocos/cocos-engine/actions/runs/13152050512

Task Details

Platform	build	boot	runned	crashScene	FailScene
windows	PASS	PASS	PASS
android	PASS	PASS	PASS
wechatgame	PASS	FAIL	FAIL