UnitTestFrameworkPkg: Add configuration for Ecc check in yaml file

Add configuration ExceptionList and IgnoreFiles for package config
files. So users can rely on this to ignore some Ecc issues.
Besides, add submodule path in IgnoreFiles section.

Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Sean Brogan <sean.brogan@microsoft.com>
Cc: Bret Barkelew <Bret.Barkelew@microsoft.com>
Signed-off-by: Shenglei Zhang <shenglei.zhang@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Michael D Kinney <michael.d.kinney@intel.com>

UnitTestFrameworkPkg/UnitTestFrameworkPkg.ci.yaml

@@ -9,6 +9,18 @@
     "LicenseCheck": {
         "IgnoreFiles": []
     },
+    "EccCheck": {
+        ## Exception sample looks like below:
+        ## "ExceptionList": [
+        ##     "<ErrorID>", "<KeyWord>"
+        ## ]
+        "ExceptionList": [
+        ],
+        ## Both file path and directory path are accepted.
+        "IgnoreFiles": [
+            "Library/CmockaLib/cmocka"
+        ]
+    },
     ## options defined .pytool/Plugin/CompilerPlugin
     "CompilerPlugin": {
         "DscPath": "UnitTestFrameworkPkg.dsc"