Fix grammar in documentation.

Remove unnecessary comma after 'both' in the sentence structure 'both A and B'. The comma between 'both' and the first item is grammatically incorrect. Original pull request #4122 Signed-off-by: Byungju Ju <wnqudwnrlrl@naver.com>

Author: GoToBILL

src/main/antora/modules/ROOT/pages/repositories/projections.adoc

@@ -28,7 +28,7 @@ Any nested properties resolving to joins select the entire nested property causi
 
 === String-based queries
 
-Support for string-based queries covers both, JPQL queries(`@Query`) and native queries (`@NativeQuery`).
+Support for string-based queries covers both JPQL queries (`@Query`) and native queries (`@NativeQuery`).
 
 ==== JPQL Queries