Icon: Remove inline style in GitHub icon to fix CSP error

[aduth]

Description

This pull request seeks to resolve an error which can occur when using the USWDS Icon component SVG sprite in combination with a Content Security Policy (CSP), where the presence of an inline style tag within the GitHub icon can violate most common CSPs which do not include the unsafe-inline style-src directive.

Additional information

The process for resolving this was to simply drop the SVG markup into the SVGOMG online SVGO optimizer tool. The produced output minified the markup and inlined the fill-rule as an HTML attribute.

An alternative solution could be to simply remove the style tag (and accompanying class attribute) and instead add the equivalent fill-rule="evenodd" attribute to the <path> element.

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Before you hit Submit, make sure you’ve done whichever of these applies to you:

• Follow the 18F Front End Coding Style Guide and Accessibility Guide.
• Run npm test and make sure the tests for the files you have changed have passed.
• Run your code through HTML_CodeSniffer and make sure it’s error free.
• Title your pull request using this format: [Website] - [UI component]: Brief statement describing what this pull request solves.

[mejiaj]

@aduth could you please include these changes in these other files too?

• src/img/uswds-icons/github.svg
• src/img/material-icons/github.svg

[aduth]

@aduth could you please include these changes in these other files too?

Sure, assuming it's the same icon, I copied the new version to replace those as well in 169e948.

[mejiaj]

Great, thanks a lot!