comma added to q2 (#286)

# Pull Request

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Fixes #247

Author: shiaoligreen

R/qenv-get_code.R

@@ -36,7 +36,7 @@
 #' _Case 2: Some objects are created by a function's side effects._
 #' ```r
 #' q2 <-
-#'   within(qenv(){
+#'   within(qenv(), {
 #'     foo <- function() {
 #'       x <<- x + 1
 #'     }