Support GIF files in Webpack config

[brendanfalkowski]

Description

Adds support for .gif files in Webpack config.

We imported a module that contains some GIF files, and buildpack threw on error about this.

Acceptance

Verification Stakeholders

Specification

Verification Steps

1. Add a GIF file to your project.
2. Import it in any component.

Screenshots / Screen Captures (if appropriate)

Checklist

• I have added tests to cover my changes, if necessary.

• I have updated the documentation accordingly, if necessary.

[PWAStudioBot]

	Fails
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[jimbo]

Yeah, it's odd that all of the other regular expressions include gif, but this one doesn't. Approved.

Also, I see you alphabetizing things.

[brendanfalkowski]

^^^ How I see myself alphabetizing things.

And how I actually look alphabetizing things:

[tjwiebell]

Tracking internally with PWA-954.

[tjwiebell]

Added a gif to local develop branch to confirm bug and got the dreaded white screen of death; checking out this branch the asset now display without error.

QA Pass ✅