chore: update package.xml version to v0.5.6 (#209)

Signed-off-by: github-actions <[email protected]>
Co-authored-by: github-actions <[email protected]>

Author: github-actions[bot]

CARET_analyze_cpp_impl/package.xml

@@ -2,7 +2,7 @@
 <?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
 <package format="3">
   <name>caret_analyze_cpp_impl</name>
-  <version>0.5.5</version>
+  <version>0.5.6</version>
   <description>c++ implementation of caret_analyze</description>
   <maintainer email="[email protected]">ymski</maintainer>
   <maintainer email="[email protected]">isp-uetsuki</maintainer>