dim-label contrast is too low
Submitted by Lukas
Link to original bug (#778516)
Description
Using the default Adwaita theme, text with the css class "dim-label" doesn't meet a11y requirements: http://leaverou.github.io/contrast-ratio/#%23828686-on-%23E8E8E7 and https://www.w3.org/TR/WCAG/#visual-audio-contrast
Since essential text is supposed to be dim (https://developer.gnome.org/hig/stable/visual-layout.html.en), we should meet these requirements.
Suggested fix: increase dim-label opacity to 0.7, results in contrast ratio of 4.5
Version: 3.22.x