[HPOS] Missing "Subscription relationship" column in the WC Orders list page

[a-danae]

Describe the bug

When HPOS is enabled, the "Subscription relationship" column is missing under the WooCommerce -> Orders page.

To Reproduce

1. Go to WooCommerce -> Settings -> Advanced -> Features. /wp-admin/admin.php?page=wc-settings&tab=advanced&section=features
2. Under Experimental features, select "High performance order storage (new)", enable "Keep the posts and orders tables in sync (compatibility mode)", and save
3. As a shopper, purchase some subscriptions if you don't have any
4. Go to WooCommerce -> Orders /wp-admin/admin.php?page=wc-orders
5. Notice the "Subscription relationship" column is missing

Expected behavior

I'd expect the "Subscription relationship" column to exist under WC -> Orders when HPOS is enabled, just as it does when HPOS is disabled.

Table when HPOS disabled:

Actual behavior

There's no "Subscription relationship" column under WC -> Orders when HPOS is enabled.

Table when HPOS is enabled:

Product impact

• [ ] Does this issue affect WooCommerce Subscriptions? yes/no/tbc, add issue ref
• [ ] Does this issue affect WooCommerce Payments? yes/no/tbc, add issue ref

Additional context

[a-danae]

Closing this as a duplicate of #469