Update whitespace usage across various docs

doc/development/api_graphql_styleguide.md

doc/development/permissions/custom_roles.md

doc/integration/advanced_search/elasticsearch.md

doc/integration/partner_marketplace.md

doc/integration/saml.md

doc/integration/sourcegraph.md

doc/user/emoji_reactions.md

doc/user/group/saml_sso/troubleshooting_scim.md

doc/user/okrs.md

doc/user/project/changelogs.md

doc/user/project/issue_board.md

doc/user/project/labels.md

doc/user/project/releases/index.md

doc/user/project/repository/mirror/bidirectional.md

doc/user/project/settings/import_export.md

doc/user/storage_management_automation.md

doc/user/usage_quotas.md