Update favicons dependency to v5.4.0

[synedra-mpe]

Favicons module has been update with many important changes, we are waiting for since Nov 2018.

https://github.com/itgalaxy/favicons/releases/tag/v5.4.0

[brunocodutra]

Thanks for the heads-up, v5.4.0 was shipped with a regression (see itgalaxy/favicons#268), as soon as v5.4.1is out (see itgalaxy/favicons#271) I'll update this plugin.

[synedra-mpe]

bump

[brunocodutra]

v2.7.1 is out #183!