fix(logger): Perform cmd subst outside heredoc

Perform function and command value substitution outside the heredoc forwarded to logger for JournalD entries.

logger.sh

@@ -107,16 +107,21 @@ writeJournalDLog() {
     return
   fi
 
+  J_TIMESTAMP="$(getTimeStamp)"
+  J_PID="$$"
+  J_PRIO="$(translateLogLevelsToJournalD "$2")"
+  J_STAT="$(uppercase "$3")"
+
   logger --journald <<end
-SYSLOG_TIMESTAMP="$(getTimeStamp)"
+SYSLOG_TIMESTAMP=${J_TIMESTAMP}
 SYSLOG_FACILITY=3
-SYSLOG_IDENTIFIER="${LOG_PROGRAM_NAME}"
+SYSLOG_IDENTIFIER=${LOG_PROGRAM_NAME}
-SYSLOG_PID="$$"
+SYSLOG_PID=${J_PID}
-PRIORITY="$(translateLogLevelsToJournalD "$2")"
+PRIORITY=${J_PRIO}
-STATUS="$(uppercase "$3")"
+STATUS=${J_STAT}
-MESSAGE="$1"
+MESSAGE=$1
-OPERATION="${4:-UNSPECIFIED}"
+OPERATION=${4:-UNSPECIFIED}
-ERRNO="${5:-999}"
+ERRNO=${5:-999}
 end
 
   return