Allow markup-ing literal strings

[xmo-odoo]

Literal strings in the application should be safe (similar to static markup in template files), and the normal way to create dynamic markup code side: create a properly marked up Markup, then Markup.format user-defined content into it.

[CLAassistant]

All committers have signed the CLA.

[xmo-odoo]

Will need to squash the PR in order to use the PR's description as commit message: had a typo ("and then normal way")

[xmo-odoo]

CI seems unhappy, even though 3.9.2 does seem available in the python-versions and #3404 seems to have fetched it fine.

Possibly a temporary network issue?

[xmo-odoo]

Aaah I think I see what the issue is, I forked off of and targeted the main branch, not sure how (since I just used github's base UI).

develop seems to be the default and correct branch to target. I retargeted the PR and rebased, and updated the commit message to fix the typo while at it. Hopefully it works better like this.

[xmo-odoo]

Right, yep, turns out using github's interface led me to not test the rule and thus forget half of it.

Also wow does the test suite not joke around. But since I was running it I added a few test cases to make sure the change actually works, probably can't hurt. Hopefully I got it right this time.

[xmo-odoo]

Thanks 🎆

[p4p3r]

Thanks for your contribution! Your changes will be available in Semgrep’s registry in a bit.