Add deprecated get_optional to Transmission Handle

[saikishor]

With #2223 we recently reverted back to the old version of the Handles in the transmission interface, however, if the user code base uses the methods get_optional and std::ignore for the set_value, he/she will have compilation issues. In order to avoid such things, I'm adding these deprecated methods only to Jazzy, so their pipelines will continue to work

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.71%. Comparing base (e84100a) to head (4b65b3e).
Report is 2 commits behind head on jazzy.

Additional details and impacted files

@@            Coverage Diff             @@
##            jazzy    #2255      +/-   ##
==========================================
+ Coverage   88.70%   88.71%   +0.01%     
==========================================
  Files         143      143              
  Lines       16437    16434       -3     
  Branches     1424     1424              
==========================================
- Hits        14581    14580       -1     
+ Misses       1311     1310       -1     
+ Partials      545      544       -1     

Flag	Coverage Δ
unittests	88.71% <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
...nterface/include/transmission_interface/handle.hpp	91.66% <100.00%> (+5.00%)	⬆️

... and 1 file with indirect coverage changes

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[christophfroehlich]

LGTM