Text error occurs on node-canvas

## Issue or Feature
- [ ] If this is an issue with installation, I have read the [troubleshooting guide](https://github.com/Automattic/node-canvas/issues/1511).

## Steps to Reproduce

```js
var Canvas = require('canvas');
var canvas = Canvas.createCanvas(500, 500);
var ctx = canvas.getContext('2d');
// etc.
```

## Your Environment
* Version of node-canvas (output of `npm list canvas` or `yarn list canvas`):
* Environment (e.g. on Win 64 Bit):
* Node-canvas : 2.10.1
* Fabric: 4.2.0

Run on Localhost (OK):

But run on Azure Function App (64 Bit) - ERROR
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I look forward to everyone's help.
Thanks all.