Dashboard icons don't pass color contrast

[melchoyce]

The Dashboard icons are mostly #82878c, which is a little too light (3.62 on white, 3.47 on #fafafa).

We could change them all to #606A73, which passes AA on both white and #fafafa, or we could do #606A73 on #fafafa and #6C7781 on white.

[chetan200891]

Created patch to change dashboard icons color.

[kjellr]

We could change them all to #606A73, which passes AA on both white and #fafafa, or we could do #606A73 on #fafafa and #6C7781 on white.

We discussed this in Design triage on slack today:
​https://wordpress.slack.com/archives/C02S78ZAL/p1563209628387100

This seems like a great change, but I'd suggest we use Mel's first suggestion here — just the single #606A73 color. The two proposed grays are generally close to each other, so it makes sense to just use one and keep things a little more consistent.

@chetan200891 would you mind updating your patch to use #606A73 in both places?

Thank you!

[chetan200891]

Updated patch.

[chetan200891]

@kjellr I have updated patch.

[kjellr]

This looks great! Thanks for the fix, @chetan200891! I think this is ready to go.

Before:

After:

[karmatosed]

In 45700:

Admin: Improve Dashboard icon contrast.

The icons used across the dashboard had too low contrast to pass AA WCAG guidelines. They’re now slightly darker for better contrast.

Props @melchoyce, @SergeyBiryukov, @chetan200891 , @kjellr
Fixes #46935