linux-quickstart: Add missing path in example git config command

Bug: Issue 7655
Change-Id: I1dea9127f28b41daa3b0f7078be29f4f2e76d6c7

Documentation/linux-quickstart.txt

diff --git a/Documentation/linux-quickstart.txt b/Documentation/linux-quickstart.txt
index 6b9374f..84deeb5 100644
--- a/Documentation/linux-quickstart.txt
+++ b/Documentation/linux-quickstart.txt
@@ -77,7 +77,7 @@
 the instance.
 
 ....
-git config --file gerrit_testsite/etc/gerrit.config httpd.listenUrl 'http://localhost:8080'
+git config --file ~/gerrit_testsite/etc/gerrit.config httpd.listenUrl 'http://localhost:8080'
 ....
 
 == Restart the Gerrit service