add parse_state_interface_descriptions and parse_command_interface_description and reuse components

[saikishor]

As we discussed in yesterday's WG meeting, as the #1688 is merged, we would like to modify the import_state_interface_descriptions and import_command_interface_descriptions instead of parsing the hardware info to them, we parse the hardware_info_.joints and hardware_info_.sensors and it imports accordingly etc

Fixes: #1766

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.92%. Comparing base (a6e44ab) to head (62e98b9).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1768      +/-   ##
==========================================
+ Coverage   86.90%   86.92%   +0.01%     
==========================================
  Files         118      118              
  Lines       11438    11423      -15     
  Branches     1051     1047       -4     
==========================================
- Hits         9940     9929      -11     
+ Misses       1131     1129       -2     
+ Partials      367      365       -2     

Flag	Coverage Δ
unittests	86.92% <100.00%> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
.../include/hardware_interface/actuator_interface.hpp	93.50% <100.00%> (-0.62%)	⬇️
...ce/include/hardware_interface/sensor_interface.hpp	93.18% <100.00%> (-0.57%)	⬇️
...ce/include/hardware_interface/system_interface.hpp	87.23% <100.00%> (-0.73%)	⬇️
hardware_interface/src/component_parser.cpp	94.60% <100.00%> (+0.17%)	⬆️

... and 1 file with indirect coverage changes

[christophfroehlich]

LGTM

[bmagyar]

In order to help with future-proofing this a little bit I am wondering if we could use a template for this function with some traits or concepts (or none if none works yet w this C++ version) to capture that we really only expect this to be an STL container, we aren't using any API specific to an unordered map

[saikishor]

Do you mean here std::unordered_map<std::string, InterfaceDescription> & state_interfaces_map ?

I'm not sure what traits can be used here. As both methods use the same set of arguments. If you have some ideas, please let me know :)