cmd/link: move comma outside quotes

Change-Id: I2ecf8976a6289924ac7bfe7ace129a462537e11d
Reviewed-on: https://go-review.googlesource.com/c/go/+/248339
Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Than McIntosh <thanm@google.com>
diff --git a/src/cmd/link/doc.go b/src/cmd/link/doc.go
index 219499b..604675c 100644
--- a/src/cmd/link/doc.go
+++ b/src/cmd/link/doc.go
@@ -3,7 +3,7 @@
 // license that can be found in the LICENSE file.
 
 /*
-Link, typically invoked as ``go tool link,'' reads the Go archive or object
+Link, typically invoked as ``go tool link'', reads the Go archive or object
 for a package main, along with its dependencies, and combines them
 into an executable binary.