chore(issues): clarify assigned_or_suggested filter (#15176)

Clarify that when using the `assigned_or_suggested` filter, issues that
are suggested but assigned to other users/teams will not appear in the
search.

Closes getsentry/sentry#40485

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## PRE-MERGE CHECKLIST

- [x] Checked Vercel preview for correctness, including links
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Author: cvxluo

docs/concepts/search/searchable-properties/issues.mdx

@@ -36,7 +36,7 @@ Returns issues assigned to the defined user(s) or team(s). Values can be a user
 
 ### `assigned_or_suggested`
 
-Returns issues that are assigned to or suggested to be assigned to the defined user(s) or team(s). Suggested assignees are found by matching [ownership rules](/product/issues/ownership-rules/) and [suspect commits](/product/issues/suspect-commits/). Values can be a user ID (your email address), `me` for yourself, `none` for no assignee/suggestion, `my_teams` or `#team-name` for teams you belong to.
+Returns issues that are either assigned to the defined user(s) or team(s), or suggested to be assigned to the defined user(s) or team(s) and are currently unassigned. Suggested assignees are found by matching [ownership rules](/product/issues/ownership-rules/) and [suspect commits](/product/issues/suspect-commits/). Values can be a user ID (your email address), `me` for yourself, `none` for no assignee/suggestion, `my_teams` or `#team-name` for teams you belong to.
 
 - **Type:** team or org user