sgdisk: add page

[godwiniheuwa]

Checklist

• The page(s) are in the correct platform directories: common, linux, osx, windows, sunos, android, etc.
• The page description(s) have links to documentation or a homepage.
• The page(s) follow the content guidelines.
• The page(s) follow the style guide.
• The PR contains at most 5 new pages.
• The PR is authored by me, or has been human-reviewed if it was created with AI or machine translation software.
• The PR title conforms to the recommended templates.
• Version of the command being documented (if known):

Closes: #19275

[tldr-bot]

The build for this PR failed with the following error(s) at commit
33d687dbfc8c8a22172615ee8a91eb2c05c5e5ca:

pages/common/sgdisk.md:3: TLDR014 Page should contain no trailing whitespace
pages/common/sgdisk.md:4: TLDR014 Page should contain no trailing whitespace

Please fix the error(s) and push again.

[Managor]

@godwiniheuwa address the issues.

[Managor]

Getting real tired of the repeated poor quality PRs for sgdisk