added multiline bash test

Author: jonashoechst

examples/RPi-OpenWRT.Pifile

@@ -26,3 +26,9 @@ RUN head -n1 "README.md"
 # test an INCLUDE - both with and without the .Pifile extension
 INCLUDE examples/Module-Hello.Pifile
 INCLUDE examples/Module-Hello
+
+# test a multiline command
+RUN sh -c "
+    echo hello
+    echo world
+"

examples/RPi-RaspberryPiOSLite.Pifile

@@ -6,3 +6,9 @@ RUN apt-get update
 RUN apt-get install -y cowsay
 
 RUN /usr/games/cowsay "huhu pimod~"
+
+# test a multiline command
+RUN bash -c "
+    echo hello
+    echo world
+"