[librsvg] Created tag 2.50.4

[Federico Mena Quintero <federico src gnome org>]

The signed tag '2.50.4' was created.

Tagger: Federico Mena Quintero <federico gnome org>
Date: 1618281434 -0500

    Tag for version 2.50.4

Changes since the last tag '2.50.3':

Federico Mena Quintero (9):
      Post-release version bump to 2.50.4
      Refactor set_style_attribute()
      Remove the style_attr String from ElementInner; fetch it from the Attributes
      Comment on the extra block in to_computed_values so it doesn't get removed by accident.
      Box a big variant in CascadedValues to use less stack space
      Remove superfluous semicolon
      (#703): Ignore elements in an error state inside the <switch> element
      Update vulnerable crates
      Update NEWS

Madds (1):
      (#698): Put limit on feMorphology radii to prevent thread hang

Sebastian Dröge (1):
      Drop temporary values earlier in SpecifiedValues::to_computed_values()