Remove non-existent vale command in style guide

[reniejoshi]

Description

Previously, the style guide instructed contributors to run pnpm lint:vale, which is a non-existent command covered by pnpm lint. This pr removes that command for the style guide table.

Closes #215.

Meta

Merge checklist:

• Pull Request title is short, imperative summary of proposed changes
• The description documents the what and why, including events that led to this PR
• Pull Request has been linted and formatted and follows the styleguide

[github-actions]

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[httphypixelnet]

Could we just create a new lint:vale command to replace the current vale command? Imo running pnpm vale should execute vale itself, not our script.