fix: add index to os cve column (#26576)

> for #26178

# Checklist for submitter

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- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
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- [x] If database migrations are included, checked table schema to
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---------

Co-authored-by: Ian Littman <iansltx@gmail.com>

changes/26178-fix-2

@@ -1,2 +1,2 @@
-- Fixed an issue with increased resource usage during vulnerabilities processing by adding a
-  database index.
+- Fixed an issue with increased resource usage during vulnerabilities processing by adding
+  database indexes.

server/datastore/mysql/migrations/tables/20250224184002_AddOSCVEIndex.go

@@ -0,0 +1,22 @@
+package tables
+
+import (
+	"database/sql"
+	"fmt"
+)
+
+func init() {
+	MigrationClient.AddMigration(Up_20250224184002, Down_20250224184002)
+}
+
+func Up_20250224184002(tx *sql.Tx) error {
+	_, err := tx.Exec(`ALTER TABLE operating_system_vulnerabilities ADD INDEX idx_os_vulnerabilities_cve (cve);`)
+	if err != nil {
+		return fmt.Errorf("failed to add index to operating_system_vulnerabilities.cve: %w", err)
+	}
+	return nil
+}
+
+func Down_20250224184002(tx *sql.Tx) error {
+	return nil
+}