Bump superbuild Micro XRCE-DDS Agent pin to v3.0.1

v3.0.0 mishandles Fast DDS 3.x's DataWriter::write() return
code (ReturnCode_t misread as bool), causing FastDDSReplier
to treat successful service replies as failed writes. Fixed
upstream in eProsima/Micro-XRCE-DDS-Agent#385.

Signed-off-by: David Laseca Perez <davidlaseca@eprosima.com>

micro_ros_agent/cmake/SuperBuild.cmake

@@ -26,7 +26,7 @@ if(NOT xrceagent_FOUND)
             GIT_REPOSITORY
                 https://github.com/eProsima/Micro-XRCE-DDS-Agent.git
             GIT_TAG
-                v3.0.0
+                v3.0.1
             PREFIX
                 ${PROJECT_BINARY_DIR}/agent
             INSTALL_DIR