Updating ReleaseNotes and cta.spec.in for CTA release 4.8.1-1/5.8.1-1

ReleaseNotes.md

-# v4.NEXT
+# v4.8.1-1
 
 ## Summary
 ### Features

cta.spec.in

@@ -587,6 +587,11 @@ echo $(jq --argjson CTA_MAJOR_VERSION $cta_major_version '. += {"cta_major_versi
 
 
 %changelog
+* Tue Dec 6 2022 Joao Afonso <joao.afonso@cern.ch> - 4.8.1-1
+- Upgrade eos4/eos5 to 4.8.94/5.1.5
+- Minor changes in preparation for next catalogue schema release
+- See ReleaseNotes.md for details
+
 * Mon Nov 28 2022 Joao Afonso <joao.afonso@cern.ch> - 4.8.0-1
 - This CTA release contains significant changes related to repacking, including the addition of new final and temporary states
 - Minor fixes and improvements to CTA