Cleanup deprecated InterpolationMethodMap

[thedevmystic]

Hello, respected maintainers, and reviewers!!
Again, this is Surya :)

This follow-up PR on interpolation_methods.hpp, cleans up the deprecated InterpolationMethodMap, for the next release cycle.

This PR addresses,

1. Removed deprecated InterpolationMethodMap.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 84.91%. Comparing base (36cfca8) to head (1abfeb0).

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #2041   +/-   ##
=======================================
  Coverage   84.91%   84.91%           
=======================================
  Files         148      148           
  Lines       14367    14367           
  Branches     1230     1230           
=======================================
  Hits        12200    12200           
  Misses       1740     1740           
  Partials      427      427           

Flag	Coverage Δ
unittests	84.91% <ø> (ø)

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

Files with missing lines	Coverage Δ
...nt_trajectory_controller/interpolation_methods.hpp	23.52% <ø> (ø)

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[fmauch]

The change itself seems fine, but what is the policy on deprecating this? Having only one sync in between seems less than what we used to do previously.

[saikishor]

The change itself seems fine, but what is the policy on deprecating this? Having only one sync in between seems less than what we used to do previously.

Yes, we will have to hold it for sometime

[thedevmystic]

Yes, I also think so. We should wait few release syncs before cleaning it up. 👍

[christophfroehlich]

Yes, that's why I labeled it as hold but will likely merge it once the deprecation got synced.
I'm just annoyed by the deprecation warning we have now, see #2019 (comment)