Docs: Remove duplicate "Legend values" heading (#75692)
* Replaced legends shared content with text
* Copy and structuring edits
* Removed redundant link
* Prettier
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(cherry picked from commit 61b856c7dc)
Signed-off-by: Jack Baldry <jack.baldry@grafana.com>
Co-authored-by: Isabel <76437239+imatwawana@users.noreply.github.com>