Update Spotlights MR template

.gitlab/merge_request_templates/add_new_software_spotlight.md

 <!--
+###############################################################################
 This is the issue template for adding new Software Spotlights.
 
 Notes
@@ -6,12 +7,17 @@ Notes
 * please do not alter the assignments and labels.
 * please add only one spotlight per merge request.
 
-If you are looking for instructions how to add a software spotlight, please visit https://hifis.net/CONTRIBUTING.html#adding-software-spotlights
+If you are looking for instructions how to add a software spotlight, please
+visit https://hifis.net/CONTRIBUTING.html#adding-software-spotlights
 
 
 Note about the preview app
 --------------------------
-Please provide us a direct link to the spotlight in the preview app. This reduces the effort for all reviewers. A template is found below. Please replace BRANCH_NAME with the name of the branch you are merging from, and <SLUG> with the slug of your spotlight. Alternatively, wait until the pipeline finished building the preview, and copy-paste the link here.
+Please provide us a direct link to the spotlight in the preview app. This
+reduces the effort for all reviewers. A template is found below. Please replace
+BRANCH_NAME with the name of the branch you are merging from, and <SLUG> with
+the slug of your spotlight. Alternatively, wait until the pipeline finished
+building the preview, and copy-paste the link here.
 
 Credentials for preview app
 ---------------------------
@@ -20,6 +26,7 @@ The credentials for the preview app are (they are publicly available, so feel fr
 
 User: hifis
 Password: HIFISReview!
+###############################################################################
 -->
 
 <!-- Delete this line and tell us about the spotlight -->
@@ -32,7 +39,9 @@ Password: HIFISReview!
 
 #### Checklist for reviewers
 
-* [ ] License is named by SPDX identifier
+* [ ] File size of images is not too large
+* [ ] Update `date_added` attribute
+* [ ] License is named by SPDX identifier if possible
 * [ ] All links are pointing to the right place
 
 /cc @frust45 @konrad @jandt-desy