Update contributor_cards.yaml

removed extraneous contriburtor cards but left one as placeholder

Author: saadarif

docs/assets/cards/contributor_cards.yaml

@@ -1,23 +1,7 @@
-- title: Artemis
+- title: Your name here!
   content: |
     [:custom-orcid:](https://orcid.org/) [:simple-github:](https://github.com/) [:simple-linkedin:](https://linkedin.com/)<br>
     Lorem ipsum dolor sit amet.
   image: ./assets/images/cards/021-artemis.png
 
-- title: Ares
-  content: |
-    [:custom-orcid:](https://orcid.org/) [:simple-github:](https://github.com/) [:simple-linkedin:](https://linkedin.com/)<br>
-    Lorem ipsum dolor sit amet.
-  image: ./assets/images/cards/006-ares.png
-
-- title: Nike
-  content: |
-    [:custom-orcid:](https://orcid.org/) [:simple-github:](https://github.com/) [:simple-linkedin:](https://linkedin.com/)<br>
-    Lorem ipsum dolor sit amet.
-  image: ./assets/images/cards/027-nike.png
 
-- title: Prometheus
-  content: |
-    [:custom-orcid:](https://orcid.org/) [:simple-github:](https://github.com/) [:simple-linkedin:](https://linkedin.com/)<br>
-    Lorem ipsum dolor sit amet.
-  image: ./assets/images/cards/019-prometheus.png