Fix accessibility violation in VersionPicker (Visible label mismatch)

[huangkevin-apr]

Why:

Closes: #42592

What's being changed (if available, include any code snippets, screenshots, or gifs):

This PR fixes an accessibility violation in the VersionPicker component where the accessible name (aria-label) did not contain the visible label text, violating WCAG 2.1 Level A (Label in Name - 2.5.3).

// Before
ariaLabel={`Select GitHub product version: current version is ${currentVersion}`}

// After  
ariaLabel={`${xs ? 'Version\n' : 'Version: '}${
  allVersions[currentVersion]?.versionTitle || t('version_picker_default_text')
}, Select GitHub product version: current version is ${currentVersion}`}

Testing

• Run accessibility audit (IBM Equal Access, axe)
• Test with screen reader (NVDA, JAWS, VoiceOver)

Fix Before

Fix After

Check off the following:

• A subject matter expert (SME) has reviewed the technical accuracy of the content in this PR. In most cases, the author can be the SME. Open source contributions may require an SME review from GitHub staff.
• The changes in this PR meet the docs fundamentals that are required for all content.
• All CI checks are passing and the changes look good in the review environment.

[github-actions]

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[github-actions]

👋 Hey there spelunker. It looks like you've modified some files that we can't accept as contributions:

• src/versions/components/VersionPicker.tsx

You'll need to revert all of the files you changed that match that list using GitHub Desktop or git checkout origin/main <file name>. Once you get those files reverted, we can continue with the review process.

The complete list of files we can't accept are:

• .devcontainer/**
• .github/**
• data/reusables/rai/**
• Dockerfile*
• src/**
• package*.json
• content/actions/how-tos/security-for-github-actions/security-hardening-your-deployments/**

We also can't accept contributions to files in the content directory with frontmatter type: rai or contentType: rai.

[github-actions]

👋 Hey there spelunker. It looks like you've modified some files that we can't accept as contributions:

• src/versions/components/VersionPicker.tsx

You'll need to revert all of the files you changed that match that list using GitHub Desktop or git checkout origin/main <file name>. Once you get those files reverted, we can continue with the review process.

The complete list of files we can't accept are:

• .devcontainer/**
• .github/**
• data/reusables/rai/**
• Dockerfile*
• src/**
• package*.json
• content/actions/how-tos/security-for-github-actions/security-hardening-your-deployments/**

We also can't accept contributions to files in the content directory with frontmatter type: rai or contentType: rai.