feat(tests): extra context in PS4

Author: tomeon

run-tests

@@ -15,6 +15,8 @@
 
 # Set colour escape sequences
 
+PS4='+ ${BASH_SOURCE:-$0}@${LINENO:-0}${FUNCNAME:+#${FUNCNAME}()}: '
+
 if [[ -n "${NO_COLOR:-}" ]] || ! colors="$(tput colors 2>/dev/null)" || (( "${colors:-0}" < 16 )); then
   RED=''
   YELLOW=''