Update sponsors.md

Author: Hubertus Tummescheit

content/events/american2024/sponsors.md

@@ -1,10 +1,8 @@
 ## Our Sponsor
 
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 |Platinum |<img src="modelon.jpg" width=400> |
 
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 |:-|:-:|:-:|:-:|:-:|
 |Gold |<img src="claytex.jpg" width=250>|<img src="3ds2.jpeg" width=250>|<img src="2020_11_04_MKTG_ESI_Logo_ColorTagline_rgb.png" width=250>|<img src="juliacomputing.jpg" width=250>|
 |Silver|<img src="maplesoft.jpg" width=250>| | |