Fast follow: Actually call upgrade_690, avoid attempt to add index twice.

[peterwilsoncc]

• Moves the call to upgrade_690() so it actually gets called
• Wraps Hello Dolly upgrade code in a version check per standard practice
• Removes the $wpdb->query() call to avoid attempting to create the new index twice, once in the upgrade and once in dbDelta().

The final item fixes a warning during upgrade: WordPress database error Duplicate key name 'type_status_author' for query ALTER TABLE wp_posts ADD INDEX type_status_author (post_type,post_status,post_author) made by wp_upgrade, upgrade_all, upgrade_690

Combined fast follows for two tickets:

• https://core.trac.wordpress.org/ticket/53323
• https://core.trac.wordpress.org/ticket/50161

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[github-actions]

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[github-actions]

The following accounts have interacted with this PR and/or linked issues. I will continue to update these lists as activity occurs. You can also manually ask me to refresh this list by adding the props-bot label.

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Props peterwilsoncc, mukesh27.

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[SergeyBiryukov]

Thanks for the PR! Merged in r60721.