Add about frame-ancestors CSP directive to readme

[mattdell]

New Features

• Add frame-ancestors to content security policy object in accordance with the Content Security Policy directives: https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/frame-ancestors

Changes and Fixes

• Modify content-security-policy.ts to accept frameAncestors or frame-ancestors
• Fixes Support for frame-ancestors #45

[codecov]

Codecov Report

Merging #46 (54e150f) into master (87f6129) will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##            master       #46   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           13        13           
  Lines          208       208           
  Branches        85        85           
=========================================
  Hits           208       208           

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[mattdell]

Must say I don't see how the code coverage is going down so much as I've added tests...! 😅

[jagaapple]

Thank you for your pull request😃
I'm busy, so I'll review this within two weeks.

This feature will be merged in v2.2.0.

[mattdell]

That's great, @jagaapple

I figured out the issue with code coverage. I had left a .only in the unit tests...! 🤦🏻‍♂️

I will also add some documentation to the README when I get a chance.

[helfi92]

Looking forward to this! 🎉

[jagaapple]

This PR is duplicated with #41 , but I will merge the README @mattdell edited about X-Frame-Options header.

Thank you!