Console error in about:fingerprintingprotection due to missing pocket module

If you open the about:fingerprintingprotection you get a console error:

downloadable font: failed to start download (font-family: "LocalFiraSans" style:normal weight:400 stretch:100 src index:0): status=2147500037 source: chrome://pocket/content/panels/fonts/FiraSans-Regular.woff

This is likely because we exclude the pocket module, but the page wants to borrow the module's font file.

Note that after ESR 140 upstream dropped pocket, and replaced this with a font file in the usercharacteristics module: https://hg-edge.mozilla.org/mozilla-central/rev/24371acd9ac3#l79.12. So we could pick out this change.

But I'm not sure if we want to bother fixing this for 15.0 or not because I'm not sure whether this page is useful for us.