UefiCpuPkg/UefiCpuPkg.ci.yaml: Ignore RISC-V file

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=4076

RISC-V register names do not follow the EDK2 formatting.
So, add it to ignore list for now.

Cc: Eric Dong <eric.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Rahul Kumar <rahul1.kumar@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sunil V L <sunilvl@ventanamicro.com>
Acked-by: Abner Chang <abner.chang@amd.com>
Reviewed-by: Andrei Warkentin <andrei.warkentin@intel.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>
Acked-by: Ray Ni <ray.ni@intel.com>

UefiCpuPkg/UefiCpuPkg.ci.yaml

@@ -27,6 +27,7 @@
         ],
         ## Both file path and directory path are accepted.
         "IgnoreFiles": [
+          "Library/BaseRiscV64CpuExceptionHandlerLib/CpuExceptionHandlerLib.h"
         ]
     },
     "CompilerPlugin": {