Use paginated tree for the last commit query

What does this MR do and why?

We don't need a tree at all for the last commit, but since the existing paginated tree returns a limited number of entries, we can use it without introducing backend changes

app/graphql/queries/repository/path_last_commit.query.graphql

@@ -6,8 +6,8 @@ query pathLastCommit($projectPath: ID!, $path: String, $ref: String!) {
       __typename
       paginatedTree(path: $path, ref: $ref) {
         __typename
-	nodes {
-	  __typename
+        nodes {
+          __typename
           lastCommit {
             __typename
             id
@@ -48,7 +48,7 @@ query pathLastCommit($projectPath: ID!, $path: String, $ref: String!) {
               }
             }
           }
-	}
+        }
       }
     }
   }