feat(SecurityHeaders): add Referrer-Policy override

[JAdshead]

Description

Allows one-app user to choose to change the Referrer-Policy header.

Motivation and Context

To enable users to change Referrer-Policy header if required.

How Has This Been Tested?

Unit tests and running locally.

Types of Changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation (adding or updating documentation)

Checklist:

• My change requires a change to the documentation and I have updated the documentation accordingly.
• These changes should be applied to a maintenance branch.
• This change requires cross browser checks.
• Performance tests should be ran against the server prior to merging.
• This change impacts caching for client browsers.
• This change impacts HTTP headers.
• This change adds additional environment variable requirements for One App users.
• I have added the Apache 2.0 license header to any new files created.

What is the Impact to Developers Using One App?

[oneamexbot]

📊 Bundle Size Report

file name	size on disk	gzip
app.js	112.6KB	31.4KB
runtime.js	15KB	5.3KB
vendors.js	128.1KB	37.9KB
app~vendors.js	405.9KB	106KB
legacy/app.js	119.4KB	33KB
legacy/runtime.js	15KB	5.3KB
legacy/vendors.js	163KB	44.8KB
legacy/app~vendors.js	412KB	107.6KB

Generated by 🚫 dangerJS against 1edc46d