docs: add VITO Remote Sensing to list of supporters (#385)

**Related Issue(s):**
N/A

**Description:**
Add VITO Remote Sensing to the list of supporters in the README.

**PR Checklist:**

- [ ] Code is formatted and linted (run `pre-commit run --all-files`)
- [ ] Tests pass (run `make test`)
- [ ] Documentation has been updated to reflect changes, if applicable
- [ ] Changes are added to the changelog

Author: StijnCaerts

README.md

@@ -25,6 +25,7 @@ The following organizations have contributed time and/or funding to support the
 <p align="left">
   <a href="https://healy-hyperspatial.github.io/"><img src="https://raw.githubusercontent.com/stac-utils/stac-fastapi-elasticsearch-opensearch/refs/heads/main/assets/hh-logo-blue.png" alt="Healy Hyperspatial" height="100" hspace="20"></a>
   <a href="https://atomicmaps.io/"><img src="https://raw.githubusercontent.com/stac-utils/stac-fastapi-elasticsearch-opensearch/refs/heads/main/assets/am-logo-black.png" alt="Atomic Maps" height="100" hspace="20"></a>
+  <a href="https://remotesensing.vito.be/"><img src="https://raw.githubusercontent.com/stac-utils/stac-fastapi-elasticsearch-opensearch/refs/heads/main/assets/VITO.png" alt="VITO Remote Sensing" height="100" hspace="20"></a>
 </p>
 
 ## Project Introduction - What is SFEOS?