CI: Add Linux headers to docker image

Signed-off-by: Brennan Ashton <bashton@brennanashton.com>
diff --git a/docker/linux/Dockerfile b/docker/linux/Dockerfile
index d0f9efe..9265611 100644
--- a/docker/linux/Dockerfile
+++ b/docker/linux/Dockerfile
@@ -230,6 +230,7 @@
   libx11-dev libx11-dev:i386 \
   libxext-dev libxext-dev:i386 \
   linux-libc-dev:i386 \
+  linux-headers-generic \
   python3 \
   python3-pip \
   python-is-python3 \
diff --git a/testlist/sim.dat b/testlist/sim.dat
index f4740da..44bdd19 100644
--- a/testlist/sim.dat
+++ b/testlist/sim.dat
@@ -20,3 +20,7 @@
 
 # macOS doesn't have ALSA
 -Darwin,sim:alsa
+
+# Do not build Linux configs
+-Darwin,sim:linux.*
+