ci: split slow tests

Allow slow tests to run as separate jobs, this should speed up CI run.

Signed-off-by: Fabio Utzig <fabio.utzig@nordicsemi.no>
diff --git a/.github/workflows/sim.yaml b/.github/workflows/sim.yaml
index c51ee84..1b6177b 100644
--- a/.github/workflows/sim.yaml
+++ b/.github/workflows/sim.yaml
@@ -7,15 +7,18 @@
       matrix:
         features:
         - "sig-ecdsa,sig-ed25519,enc-kw,bootstrap"
-        - ",sig-rsa,sig-rsa3072,overwrite-only,validate-primary-slot,swap-move"
-        - "enc-rsa,enc-ec256,enc-x25519"
+        - "sig-rsa,sig-rsa3072,overwrite-only,validate-primary-slot,swap-move"
+        - "enc-rsa"
+        - "enc-ec256"
+        - "enc-x25519"
         - "sig-rsa overwrite-only large-write,sig-ecdsa overwrite-only large-write,multiimage overwrite-only large-write"
         - "sig-rsa validate-primary-slot,sig-ecdsa validate-primary-slot,sig-rsa multiimage validate-primary-slot"
         - "enc-kw overwrite-only large-write,enc-rsa overwrite-only large-write"
         - "sig-rsa enc-rsa validate-primary-slot,swap-move enc-rsa sig-rsa validate-primary-slot"
         - "sig-rsa enc-kw validate-primary-slot bootstrap,sig-ed25519 enc-x25519 validate-primary-slot"
         - "sig-ecdsa enc-kw validate-primary-slot"
-        - "sig-rsa validate-primary-slot overwrite-only large-write,sig-ecdsa enc-ec256 validate-primary-slot"
+        - "sig-rsa validate-primary-slot overwrite-only large-write"
+        - "sig-ecdsa enc-ec256 validate-primary-slot"
         - "sig-rsa validate-primary-slot overwrite-only downgrade-prevention"
     name: Sim
     runs-on: ubuntu-latest