v0.12.1

NLPModelsJuMP v0.12.1

Diff since v0.12.0

Merged pull requests:

• Add more warning from QuadExpr (#139) (@amontoison)
• Update CommentPR.yml (#141) (@amontoison)
• Add discussion in readme (#142) (@tmigot)
• Bump to NLPModels 0.20 (#146) (@tmigot)
• [CI] Update .cirrus.yml (#147) (@amontoison)
• Version 0.12.1 (#148) (@tmigot)