Create GOPATH within WORKSPACE, rather home directory. Clarify docs

Change-Id: Ie94c2ed9ab096b4c34065971492a44454b172675
diff --git a/jjb/shell/github-release.sh b/jjb/shell/github-release.sh
index 1e31421..2ab2c94 100644
--- a/jjb/shell/github-release.sh
+++ b/jjb/shell/github-release.sh
@@ -56,18 +56,18 @@
 
 # To support golang projects create a GOPATH
 # If $DEST_GOPATH is not an empty string:
-# - set create GOPATH, and destination directory within in
+# - create GOPATH within WORKSPACE, and destination directory within
 # - set PATH to include $GOPATH/bin and the system go binaries
-# - symlink from $WORKSPACE/$GERRIT_PROJECT to new location in $GOPATH
-# - start release from that directory
+# - move project from $WORKSPACE/$GERRIT_PROJECT to new location in $GOPATH
+# - start release process within that directory
 
 DEST_GOPATH=${DEST_GOPATH:-}
 if [ ! -z "$DEST_GOPATH" ]; then
-  export GOPATH=${GOPATH:-~/go}
+  export GOPATH=${GOPATH:-$WORKSPACE/go}
   mkdir -p "$GOPATH/src/$DEST_GOPATH"
   export PATH=$PATH:/usr/lib/go-1.12/bin:/usr/local/go/bin:$GOPATH/bin
   release_path="$GOPATH/src/$DEST_GOPATH/$GERRIT_PROJECT"
-  ln -r -s "$WORKSPACE/$GERRIT_PROJECT" "$release_path"
+  mv "$WORKSPACE/$GERRIT_PROJECT" "$release_path"
 else
   release_path="$WORKSPACE/$GERRIT_PROJECT"
 fi