fix build script

.drone.sh

@@ -9,7 +9,7 @@ echo $now
 #ls -lah ~
 #go env
 echo "build commences"
-go build -ldflags "-X main.sha1ver=`git rev-parse HEAD` -X main.buildTime=$now" -o json2excel
+go build -ldflags "-X main.sha1ver=`git rev-parse HEAD` -X main.buildTime=$now" -o json2excel ./cmd/main/main.go
 echo "build complete"
 sha256sum json2excel > json2excel_checksum.txt
 ls -lah