Fix MySQL 8 upgrade script to schema v1.3 (#4598)

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**What changed?**
Fixed MySQL 8 upgrade script to schema v1.3.

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**Why?**


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test? Checked in staging env? -->
**How did you test it?**
Started Server with MySQL 8, and ran a workflow. Before, it was throwing
visibility errors, now it doesn't.

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**Potential risks**
No.

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**Is hotfix candidate?**
Yes

schema/mysql/v8/visibility/versioned/v1.3/add_build_ids_search_attribute.sql

@@ -1,2 +1,2 @@
-ALTER TABLE executions_visibility ADD COLUMN BuildIds JSON GENERATED ALWAYS AS (search_attributes->'BuildIds');
+ALTER TABLE executions_visibility ADD COLUMN BuildIds JSON GENERATED ALWAYS AS (search_attributes->'$.BuildIds');
 CREATE INDEX by_build_ids ON executions_visibility (namespace_id, (CAST(BuildIds AS CHAR(255) ARRAY)), (COALESCE(close_time, CAST('9999-12-31 23:59:59' AS DATETIME))) DESC, start_time DESC, run_id);