Remove ignore for real_time.md

Author: Felix Exner

.github/workflows/ci.yml

@@ -100,7 +100,6 @@ jobs:
             --exclude-dir=CMakeModules \
             --exclude=tcp_socket.cpp \
             --exclude-dir=debian \
-            --exclude=real_time.md \
             --exclude=dataflow.graphml \
             --exclude=start_ursim.sh