testlist: Add /arm/rp2040 to arm-04.dat

Summary:
- This commit adds /arm/rp2040 to arm-04.dat

Impact:
- None

Testing:
- Tested with $ ./cibuild.sh -A -c testlist/arm-04.dat
diff --git a/testlist/arm-04.dat b/testlist/arm-04.dat
index 093ac27..532f290 100644
--- a/testlist/arm-04.dat
+++ b/testlist/arm-04.dat
@@ -17,3 +17,4 @@
 
 /arm/nuc1xx,CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIL
 
+/arm/rp2040,CONFIG_ARMV7M_TOOLCHAIN_GNU_EABIL