tools/gopls: small fixes to contributing.md

Change-Id: I261e1936b96e70ad8347655a7a8d0eb792348d44
Reviewed-on: https://go-review.googlesource.com/c/tools/+/330853
Trust: Jean de Klerk <deklerk@google.com>
Run-TryBot: Jean de Klerk <deklerk@google.com>
gopls-CI: kokoro <noreply+kokoro@google.com>
Reviewed-by: Robert Findley <rfindley@google.com>
diff --git a/gopls/doc/contributing.md b/gopls/doc/contributing.md
index 8229eca..307b601 100644
--- a/gopls/doc/contributing.md
+++ b/gopls/doc/contributing.md
@@ -109,8 +109,10 @@
 
 ## Debugging
 
-The easiest way to debug your change is to run can run a single `gopls` test
-with a debugger.
+The easiest way to debug your change is to run a single `gopls` test with a
+debugger.
+
+See also [Troubleshooting](troubleshooting.md#troubleshooting).
 
 <!--TODO(rstambler): Add more details about the debug server and viewing
 telemetry.-->