build: remove old Travis references

We no longer use Travis.

Dockerfile

@@ -1,5 +1,4 @@
 # If you change this value, please change it in the following files as well:
-# /.travis.yml
 # /dev.Dockerfile
 # /make/builder.Dockerfile
 # /.github/workflows/main.yml

dev.Dockerfile

@@ -1,5 +1,4 @@
 # If you change this value, please change it in the following files as well:
-# /.travis.yml
 # /Dockerfile
 # /make/builder.Dockerfile
 # /.github/workflows/main.yml

lnrpc/README.md

@@ -1,7 +1,6 @@
 lnrpc
 =====
 
-[![Build Status](http://img.shields.io/travis/lightningnetwork/lnd.svg)](https://travis-ci.org/lightningnetwork/lnd) 
 [![MIT licensed](https://img.shields.io/badge/license-MIT-blue.svg)](https://github.com/lightningnetwork/lnd/blob/master/LICENSE)
 [![GoDoc](https://img.shields.io/badge/godoc-reference-blue.svg)](http://godoc.org/github.com/lightningnetwork/lnd/lnrpc)
 

make/builder.Dockerfile

@@ -1,5 +1,4 @@
 # If you change this value, please change it in the following files as well:
-# /.travis.yml
 # /Dockerfile
 # /dev.Dockerfile
 # /.github/workflows/main.yml