#### Describe the bug
For some REST API endpoints we use [Google Cloud API Custom Methods](https://cloud.google.com/apis/design/custom_methods) URL design like `/api/resource:customVerb`.

These worked with `axios` prior to **0.27.1** but now they result in an error like:

`AxiosError { message: "Unsupported protocol /api/resource:', code: "ERR_BAD_REQUEST", ... }`

#### To Reproduce
Try to have `axios` get a relative URL with a colon in it, e.g.
```js
axios.get("/api/resource:customVerb");
```

#### Expected behavior
Should continue working as it did before version **0.27.1**.

#### Environment
 - Axios Version: 0.27.1
 - Browser: Microsoft Edge 100.0.1185.50
 - Node.js Version: 16.14.2
 - OS: Windows 10 Pro

#### Additional context/Screenshots
n/a

lib/adapters/xhr.js
'use strict';
var utils = require('./../utils');
var settle = require('./../core/settle');
var cookies = require('./../helpers/cookies');
var buildURL = require('./../helpers/buildURL');
var buildFullPath = require('../core/buildFullPath');
var parseHeaders = require('./../helpers/parseHeaders');
var isURLSameOrigin = require('./../helpers/isURLSameOrigin');
var transitionalDefaults = require('../defaults/transitional');
var AxiosError = require('../core/AxiosError');
var CanceledError = require('../cancel/CanceledError');
module.exports = function xhrAdapter(config) {
  return new Promise(function dispatchXhrRequest(resolve, reject) {
    var requestData = config.data;
    var requestHeaders = config.headers;
    var responseType = config.responseType;
    var onCanceled;
    function done() {