Skip the Existing Ignore Paths

[soroushysfi]

I have a couple of ignore paths mentioned in my .template-lintrc.js file. These ignore paths are fetched by the linto-to-the-future package and cause the following error. This error is thrown when I run npx lint-to-the-future ignore after installing the packages:

(node:22185) UnhandledPromiseRejectionWarning: TypeError: Expected input to be a string
    at Function.picomatch.test (/Project/node_modules/picomatch/lib/picomatch.js:119:11)
    at matcher (/Project/node_modules/picomatch/lib/picomatch.js:67:50)
    at /Project/node_modules/ember-template-lint/lib/-private/module-status-cache.js:33:61
    at Array.find (<anonymous>)
    at ModuleStatusCache.lookupIgnore (/Project/node_modules/ember-template-lint/lib/-private/module-status-cache.js:33:45)
    at ModuleStatusCache.getConfigForFile (/Project/node_modules/ember-template-lint/lib/-private/module-status-cache.js:73:26)
    at Linter.verify (/Project/node_modules/ember-template-lint/lib/linter.js:308:46)
    at /Project/node_modules/lint-to-the-future-ember-template/main.js:46:26
    at Array.forEach (<anonymous>)
    at Proxy.ignoreAll (/Project/node_modules/lint-to-the-future-ember-template/main.js:41:9)
(node:22185) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). To terminate the node process on unhandled promise rejection, use the CLI flag `--unhandled-rejections=strict` (see https://nodejs.org/api/cli.html#cli_unhandled_rejections_mode). (rejection id: 174)

I believe this error is thrown from the picomatch package when trying to fetch ignore paths with an undefined input. The error thrown from the picomatch package (picomatch.js line 118):

  if (typeof input !== 'string') {
    throw new TypeError('Expected input to be a string');
  }