Density - Publish 1.0 with PhET-iO

[markgammon]

Publish Density simulation with both PhET and PhET-iO brands.

• Density Main checklist #1
• PhET-iO Design Review #76

[zepumph]

This is published, but we are going to do a MR that includes these three improvements:

• https://github.com/phetsims/studio/issues/243
• https://github.com/phetsims/studio/issues/245
• https://github.com/phetsims/phet-io/issues/1835
• https://github.com/phetsims/studio/issues/250
• https://github.com/phetsims/studio/issues/253
• https://github.com/phetsims/phet-io/issues/1842 (potentially)

UPDATE from @samreid
We may have things to cherry-pick from:

• https://github.com/phetsims/studio/issues/246
• https://github.com/phetsims/studio/issues/252
• https://github.com/phetsims/phet-io-client-guides/issues/19

[samreid]

I moved this back from "done" to "in progress" for the project board.

[zepumph]

We have since moved away from a Maintenance Release, we are instead working towards a batch release from master, see https://github.com/orgs/phetsims/projects/44

[arouinfar]

We published 1.0 in January 2022 and opened #108 for the 1.1 publication. We can close this issue.