Add: J-Spring

Adding J-Spring incl CFP

README.md

@@ -407,6 +407,7 @@ All the data (past and coming) are available publicly in JSON:
 * 3: [APIdays Helsinki and North](https://www.apidays.global/helsinki_and_north/) - Helsinki (Finland) <a href="https://apidays.typeform.com/to/ILJeAaV8"><img alt="CFP API Days Helsinki and North" src="https://img.shields.io/static/v1?label=CFP&message=until%2003-May-2025&color=green"></a>
 * 4-5: [DevTalks Romania](https://www.devtalks.ro/) -  Bucharest (Romania) <a href="https://www.papercall.io/devtalksromania-2025"><img alt="CFP DevTalks Romania" src="https://img.shields.io/static/v1?label=CFP&message=until%2004-June-2025&color=green"></a>
 * 5: [Conf42.com Observability 2025](https://www.conf42.com/obs2025) - Online <a href="https://www.papercall.io/conf42-observability-2025"><img alt="CFP Conf42.com Observability 2025" src="https://img.shields.io/static/v1?label=CFP&message=until%2005-May-2025&color=green"></a>
+* 5: [J-Spring](https://jspring.nl/) - Utrecht (Netherlands) <a href="https://sessionize.com/jspring25"><img alt="CFP J-Spring" src="https://img.shields.io/static/v1?label=CFP&message=until%2015-April-2025&color=green"></a>
 * 5-6: [KCD Czech & Slovak - Bratislava 2025](https://community.cncf.io/events/details/cncf-kcd-czech-slovak-presents-kcd-czech-amp-slovak-bratislava-2025/) - Bratislava (Slovakia) <a href="https://sessionize.com/kcd-czech-slovak-2025"><img alt="CFP KCD Czech 2025" src="https://img.shields.io/static/v1?label=CFP&message=until%2014-March-2025&color=green"></a>
 * 5-6: [AlpesCraft](https://www.alpescraft.fr/) - Grenoble (France)
 * 5-6: [Devquest 2025](https://www.devquest.fr/) - Niort (France) <a href="https://conference-hall.io/devquest-2025"><img alt="CFP Devquest 2025" src="https://img.shields.io/static/v1?label=CFP&message=until%2016-March-2025&color=green"></a>