Make asides less prominent

[illright]

Description

Related to #1701

This PR changes the appearance of aside blocks to make them stand out less. This was done by changing the -low version of the color palette to be less prominent. This change also affected the Card component.

I based my changes off of HiDeoo's WIP branch, but left off some changes:

• decided not to round the corners of asides, since this is something that should be done separately and consistently
• decided not to reduce the icon size because it didn't seem necessary
• instead of using color-mix to add transparency to existing -low colors, I decided to change the low colors to keep consistency

Screenshots of the before/after for asides and cards in dark/light mode

	Before	After
Asides (dark)
Asides (light)
Cards (dark)
Cards (light)

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🦋 Changeset detected

Latest commit: 83118bf

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

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[delucis]

Thanks for this and your other PRs @illright!

As a heads up, the changes proposed in #1701 were not 100% finalised/agreed upon, so a review may take a bit of time.

We’re currently focusing our efforts on getting the Astro v5-compatible release of Starlight ready, so please understand if it takes some time to get back to you on these.