Remove explicit "default" test config argument.

Not specifying the test config implicitly selects default args.

.github/configs

@@ -9,6 +9,9 @@
 # LTESTS
 
 config=$1
+if [ "$config" = "" ]; then
+	config="default"
+fi
 
 unset CC CFLAGS CPPFLAGS LDFLAGS LTESTS SUDO
 

.github/workflows/selfhosted.yml

@@ -50,8 +50,6 @@ jobs:
           - sol10
           - sol11
           - win10
-        configs:
-          - default
         # Then we include any extra configs we want to test for specific VMs.
         include:
           - { os: ARM64,  configs: pam }