docs: disclaimer for EOL in readme (#1663)

* docs: eol in README

Signed-off-by: Meg McRoberts <meg.mcroberts@dynatrace.com>

* remove disclaimer

Signed-off-by: Meg McRoberts <meg.mcroberts@dynatrace.com>

* docs: disclaimer for EOL in README

Signed-off-by: Meg McRoberts <meg.mcroberts@dynatrace.com>

* Update README.md

Co-authored-by: RealAnna <89971034+RealAnna@users.noreply.github.com>
Signed-off-by: Giovanni Liva <giovanni.liva@dynatrace.com>

---------

Signed-off-by: Meg McRoberts <meg.mcroberts@dynatrace.com>
Signed-off-by: Giovanni Liva <giovanni.liva@dynatrace.com>
Co-authored-by: Giovanni Liva <giovanni.liva@dynatrace.com>
Co-authored-by: RealAnna <89971034+RealAnna@users.noreply.github.com>

README.md

@@ -1,5 +1,8 @@
 # Keptn Website
 
+## Keptn V1 has reached end of life on December 22nd, 2023 and has been [replaced](https://github.com/keptn/lifecycle-toolkit).
+
+
 [![Channel on Slack](https://img.shields.io/badge/Slack-%23keptn--website-green)](https://v1.keptn.sh/community/#slack)
 ![Powered by Netlify](https://img.shields.io/netlify/5b8b8c0a-121b-4216-bf17-eec11b2f2391)