Sponsors: add emsys

cc @sscherfke

Author: hynek

README.md

@@ -42,6 +42,7 @@ for sponsor in tomllib.loads(pathlib.Path("pyproject.toml").read_text())["tool"]
 <a href="https://www.variomedia.de/"><img title="Variomedia AG" src="docs/_static/sponsors/Variomedia.svg" width="190" /></a>
 <a href="https://tidelift.com/?utm_source=lifter&utm_medium=referral&utm_campaign=hynek"><img title="Tidelift" src="docs/_static/sponsors/Tidelift.svg" width="190" /></a>
 <a href="https://klaviyo.com/"><img title="Klaviyo" src="docs/_static/sponsors/Klaviyo.svg" width="190" /></a>
+<a href="https://www.emsys-renewables.com/"><img title="emsys renewables" src="docs/_static/sponsors/emsys-renewables.svg" width="190" /></a>
 <a href="https://filepreviews.io/"><img title="FilePreviews" src="docs/_static/sponsors/FilePreviews.svg" width="190" /></a>
 <a href="https://polar.sh/"><img title="Polar" src="docs/_static/sponsors/Polar.svg" width="190" /></a>
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