[feature]: allow blob: types for style-src

[mrbash]

Fix issue #2979

Description

Added 'blob' keyword to veniaSecurityHeaders default template, enabling the load of blob stylesheet contents under CSP constraints.

Related Issue

Closes #2979

Acceptance

Verification Stakeholders

Specification

Verification Steps

1. yarn build
2. yarn start
3. verify that blob stylesheet is loading without browser csp errors

Screenshots / Screen Captures (if appropriate)

Checklist

• I have added tests to cover my changes, if necessary.
• I have added translations for new strings, if necessary.
• I have updated the documentation accordingly, if necessary.

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[sirugh]

Thanks! Verified using my local instance.

[sirugh]

@mrbash would you mind signing the Adobe CLA? We need that before we can merge your PR. Just click the "Details" next to the Adobe CLA check below.

[mrbash]

@mrbash would you mind signing the Adobe CLA? We need that before we can merge your PR. Just click the "Details" next to the Adobe CLA check below.

@sirugh
Done!