docs: ensure table headers are lintable

[thompson-tomo]

Which problem is this PR solving?

• This ensures that tables can still be linted once markdownlint is updated

Short description of the changes

• Ensures that tables are using the aligned style including the seperator row.

[github-actions]

This package does not have an assigned component owner and is considered unmaintained. As such this package is in feature-freeze and this PR will be closed with 14 days unless a new owner or a sponsor (a member of @open-telemetry/javascript-approvers) for the feature is found. It is the responsibility of the author to find a sponsor for this feature.
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[otelbot]

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