Update `jj edit <commit>` to add commit into view heads if not already

[kevincliao]

jj new <commit> automatically adds the checked out commits into the view head ids. However, jj edit does not.

To reproduce:

jj git init test
cd test
jj commit -m "my commit"
jj log -r @- -T commit_id # Save the id
jj abandon -r @-
jj edit <saved_id>

jj log -r :: # Does not show the currently editing commit 

Checklist

If applicable:

• [x] I have updated CHANGELOG.md
• [ ] I have updated the documentation (README.md, docs/, demos/)
• [ ] I have updated the config schema (cli/src/config-schema.json)
• [x] I have added tests to cover my changes