Intent to ship: CSP3 subset of script-src-elem, script-src-attr, style-src-elem and style-src-attr

[Tom Schuster]

We plan on shipping these features in Firefox 108.

We had a previous intent to prototype and ship for these features, but
we didn't ship them at that point because of a missing entry in the
standards position database:
https://github.com/mozilla/standards-positions/issues/666.

Bug to turn on by default: https://bugzilla.mozilla.org/show_bug.cgi?id=1782513
Standard: https://github.com/w3c/webappsec-csp/pull/325 and
https://w3c.github.io/webappsec-csp/#directives-fetch (See
script-src-elem etc.)
The feature was previously discussed in:
https://groups.google.com/a/mozilla.org/g/dev-platform/c/LlxUr3vIBWc/m/KWWGA2qmAAAJ

Thanks