Move author list into frontmatter (spherex sdt)

Author: troyraen

tutorials/spherex/spherex_source_discovery/spherex_source_discovery_tool_demo.md

@@ -9,6 +9,13 @@ kernelspec:
   display_name: Python 3 (ipykernel)
   language: python
   name: python3
+authors:
+  - name: Gabriela Torrini
+  - name: Andreas Faisst
+  - name: SPHEREx Science Data Center (SSDC)
+  - name: Troy Raen
+  - name: Brigitta Sipőcz
+  - name: Jaladh Singhal
 ---
 
 # SPHEREx Source Discovery Tool IRSA Demo
@@ -819,8 +826,6 @@ This work has made use of the NASA/IPAC Infrared Science Archive, which is funde
 
 ## About this Notebook
 
-**Authors:** Gabriela Torrini, Andreas Faisst, and the SPHEREx Science Data Center (SSDC); Troy Raen, Brigitta Sipőcz, and Jaladh Singhal
-
 **Contact:** [IRSA Helpdesk](https://irsa.ipac.caltech.edu/docs/help_desk.html) with questions
 or problems.