fix: updated internal switch schema

https://telecominfraproject.atlassian.net/browse/OLS-433

Summary of changes:
- Updated internal switch schema.

Signed-off-by: Ivan Chvets <ivan.chvets@kinarasystems.com>

src/framework/ConfigurationValidator.cpp

@@ -376,6 +376,8 @@ static std::string DefaultAPSchema = R"foo(
             "properties": {
                 "port-mirror": {
                     "description": "Enable mirror of traffic from multiple minotor ports to a single analysis port.",
+                    "type": "array",
+                    "items": {
                         "type": "object",
                         "properties": {
                             "monitor-ports": {
@@ -390,6 +392,7 @@ static std::string DefaultAPSchema = R"foo(
                                 "type": "string"
                             }
                         }
+                    }
                 },
                 "loop-detection": {
                     "description": "Enable loop detection on the L2 switches/bridge.",