Fix MRP SessionIdleInterval per spec to 500ms

Spec has the default SESSION_IDLE_INTERVAL defined as 500ms
https://github.com/CHIP-Specifications/connectedhomeip-spec/blob/1.2/src/secure_channel/Message_Reliability_MRP.adoc#8-parameters-and-constants

Originally defined as 300ms, this change was introduced as part of spec PR
CHIP-Specifications/connectedhomeip-spec#7186

Author: samadDotDev

src/app/tests/suites/certification/Test_TC_SC_4_10.yaml

@@ -42,7 +42,7 @@ tests:
       verification: |
           avahi-browse -rt _matter._tcp
           On the TH(Chip-tool) Log: Verify the DUT is advertising for:
-          -SII key is higher than the SLEEPY_IDLE_INTERVAL default value (> 300 milliseconds)
+          - SII key is higher than the SLEEPY_IDLE_INTERVAL default value (> 500 milliseconds)
           - SII key and SAI key is less than 3600000 (1hour in milliseconds)
 
           +   eth0 IPv6 3A235FF3FA2DAC10-0000000000000055             _matter._tcp         local

src/messaging/ReliableMessageProtocolConfig.cpp

@@ -60,8 +60,8 @@ void ClearLocalMRPConfigOverride()
 
 ReliableMessageProtocolConfig GetDefaultMRPConfig()
 {
-    // Default MRP intervals are defined in spec <2.11.3. Parameters and Constants>
-    static constexpr const System::Clock::Milliseconds32 idleRetransTimeout   = 300_ms32;
+    // Default MRP intervals are defined in spec <4.12.8. Parameters and Constants>
+    static constexpr const System::Clock::Milliseconds32 idleRetransTimeout   = 500_ms32;
     static constexpr const System::Clock::Milliseconds32 activeRetransTimeout = 300_ms32;
     static constexpr const System::Clock::Milliseconds16 activeThresholdTime  = 4000_ms16;
     return ReliableMessageProtocolConfig(idleRetransTimeout, activeRetransTimeout, activeThresholdTime);

src/messaging/ReliableMessageProtocolConfig.h

@@ -84,7 +84,7 @@ namespace chip {
 #if CHIP_ENABLE_OPENTHREAD && !CHIP_DEVICE_LAYER_TARGET_LINUX
 #define CHIP_CONFIG_MRP_LOCAL_IDLE_RETRY_INTERVAL (800_ms32)
 #else
-#define CHIP_CONFIG_MRP_LOCAL_IDLE_RETRY_INTERVAL (300_ms32)
+#define CHIP_CONFIG_MRP_LOCAL_IDLE_RETRY_INTERVAL (500_ms32)
 #endif
 #endif // CHIP_CONFIG_MRP_LOCAL_IDLE_RETRY_INTERVAL && !CHIP_DEVICE_LAYER_TARGET_LINUX
 

src/messaging/tests/MessagingContext.h

@@ -78,7 +78,7 @@ class MessagingContext : public PlatformMemoryUser
     enum MRPMode
     {
         kDefault = 1, // This adopts the default MRP values for idle/active as per the spec.
-                      //      i.e IDLE = 4s, ACTIVE = 300ms
+                      //      i.e IDLE = 500ms, ACTIVE = 300ms
 
         kResponsive = 2, // This adopts values that are better suited for loopback tests that
                          // don't actually go over a network interface, and are tuned much lower