If you want to Unstage a Staged file before Commit:
git reset HEAD fileToUnstage
Git How-To Display Staged Vs Un-staged Changes
$schemamarkup = get_post_meta(get_the_ID(), 'schemamarkup', true); if(!empty($schemamarkup)) { echo $schemamarkup; }
If you want to Unstage a Staged file before Commit:
git reset HEAD fileToUnstage