feat: add release testing label for all repos (#506)

edx_repo_tools/repo_checks/labels.yaml

@@ -18,10 +18,12 @@
 
 ### LABELS USED FOR MANAGING A TEMPORARY STATE OR
 ### PROBLEM ACROSS REPOSITORIES
+
 - name: "business-specific"
   color: "d93f0b"  # scarlet red...
   description: "Code that relates to a specific user and should be refactored and removed."
 
+
 ### LABELS INDICATING HOW ISSUES CAN BE ENAGAGED WITH.
 
 - name: "good first issue"
@@ -32,6 +34,10 @@
   color: "54976d"  # fenway green
   description: "Ready to be picked up by anyone in the community"
 
+- name: "release testing"
+  color: "ff00ff"  # magenta
+  description: "Affects the upcoming release (attention needed)"
+
 
 ### LABELS INDICATING BROAD THEMES OF WORK.
 ### MORE THAN ONE OF THESE MAY APPLY AT A TIME.