[Merged by Bors] - chore(ring_theory/kaehler): cleanup instances

[eric-wieser]

The previous module instance has the wrong defeqs, and was more work to construct. The new one remains propositionally equal to the old one.

---

[riccardobrasca]

Thanks!

bors merge

[bors[bot]]

Pull request successfully merged into master.

Build succeeded!

The publicly hosted instance of bors-ng is deprecated and will go away soon.

If you want to self-host your own instance, instructions are here. For more help, visit the forum.

If you want to switch to GitHub's built-in merge queue, visit their help page.

• Build mathlib
• Lint mathlib
• Lint style
• Run tests