Update coreMQTT submodule pointer to latest commit (#1934)

* Update coreMQTT submodule pointer to latest commit

* Change the path of the .tag file for the coreMQTT library

* Update coreMQTT Submodule Pointer to the Latest commmit with coverity updates

Author: DakshitBabbar

docs/doxygen/config.doxyfile

@@ -2337,7 +2337,7 @@ SKIP_FUNCTION_MACROS   = YES
 # the path). If a tag file is not located in the directory in which doxygen is
 # run, you must also specify the path to the tagfile here.
 
-TAGFILES               = libraries/standard/coreMQTT/docs/doxygen/output/mqtt.tag=../../../../libraries/standard/coreMQTT/docs/doxygen/output/html \
+TAGFILES               = libraries/standard/coreMQTT/docs/doxygen/output/html/mqtt.tag=../../../../libraries/standard/coreMQTT/docs/doxygen/output/html \
                          libraries/standard/coreJSON/docs/doxygen/output/json.tag=../../../../libraries/standard/coreJSON/docs/doxygen/output/html \
                          libraries/standard/corePKCS11/docs/doxygen/output/core_pkcs11.tag=../../../../libraries/standard/corePKCS11/docs/doxygen/output/html \
                          libraries/aws/device-shadow-for-aws-iot-embedded-sdk/docs/doxygen/output/shadow.tag=../../../../libraries/aws/device-shadow-for-aws-iot-embedded-sdk/docs/doxygen/output/html \

libraries/standard/coreMQTT

@@ -8,7 +8,7 @@ description: |-
   See dependencies for included libraries."
 dependencies:
   - name: "coreMQTT"
-    version: "v2.3.1"
+    version: "86a5750bb31e05fa69ef3f4e2f5e69d9317fae44"
     repository:
       type: "git"
       url: "https://github.com/FreeRTOS/coreMQTT"