docs: fix plural form

Addresses: https://github.com/systemd/systemd/pull/36133#discussion_r1932816287

diff --git a/docs/USER_GROUP_API.md b/docs/USER_GROUP_API.md
index e0f786ad899bd5fd3281806d10b471d1804dc3c5..fdb7b6568c61fe0a719b2fbf8913ef5a8c362fb6 100644 (file)
--- a/docs/USER_GROUP_API.md
+++ b/docs/USER_GROUP_API.md
@@ -248,7 +248,7 @@ Or to say this differently: the *primary search keys* are
 either of the primary search keys are found `NoRecordFound()` is returned. If
 one is found that matches one but not the other primary search key
 `ConflictingRecordFound()` is returned. If an entry is found that matches the
-primary search key, but not the secondary match filters
+primary search keys, but not the secondary match filters
 `NonMatchingRecordFound()` is returned. Finally, if an entry is found that
 matches both the primary search keys and the secondary search filters, they are
 returned as successful response. Note that both the primary search keys and the