fix: add slot=label attribute as legit use-case for the deprecated Label

[knoobie]

Description

To reduce the false positive warnings when the deprecated Label component is used by the flow-components with proper client-side logic to associate the field with the Label. The attribute slot=label is also added to the list of valid use-cases.

Related to vaadin/flow-components#5171 and #16708 (comment)

Type of change

• Bugfix
• Feature

Checklist

• I have read the contribution guide: https://vaadin.com/docs/latest/guide/contributing/overview/
• I have added a description following the guideline.
• The issue is created in the corresponding repository and I have referenced it.
• I have added tests to ensure my change is effective and works as intended.
• New and existing tests are passing locally with my change.
• I have performed self-review and corrected misspellings.

Additional for Feature type of change

• Enhancement / new feature was discussed in a corresponding GitHub issue and Acceptance Criteria were created.

[sonarqubecloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
5 Code Smells

No Coverage information
0.0% Duplication

[github-actions]

Test Results

   996 files  ±0     996 suites  ±0   1h 4m 16s ⏱️ - 1m 4s
6 336 tests ±0  6 295 ✔️ ±0  41 💤 ±0  0 ❌ ±0 
6 593 runs  +1  6 545 ✔️ +1  48 💤 ±0  0 ❌ ±0 

Results for commit f23d636. ± Comparison against base commit 319e98d.

[mcollovati]

@knoobie Thanks for the contribution!

[vaadin-bot]

This ticket/PR has been released with Vaadin 24.2.0.alpha1 and is also targeting the upcoming stable 24.2.0 version.