[WIP] Keep symbolic expressions from mtk, make it moi compatible later

[Vaibhavdixit02]

Checklist

• [] Appropriate tests were added
• [] Any code changes were done in a way that does not break public API
• [] All documentation related to code changes were updated
• [] The new code follows the contributor guidelines, in particular the ScioML Style Guide and COLPRAC.
• [] Any new documentation only uses public API

Additional context

Add any other context about the problem here.

[codecov[bot]]

Codecov Report

Attention: 89 lines in your changes are missing coverage. Please review.

Comparison is base (6fc5804) 0.00% compared to head (75d197b) 7.47%. Report is 1 commits behind head on master.

Files	Patch %	Lines
lib/OptimizationMOI/src/OptimizationMOI.jl	0.00%	49 Missing :warning:
lib/OptimizationMOI/src/nlp.jl	0.00%	28 Missing :warning:
lib/OptimizationMOI/src/moi.jl	0.00%	12 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #636 +/- ## ========================================= + Coverage 0.00% 7.47% +7.47% ========================================= Files 12 40 +28 Lines 1141 2730 +1589 ========================================= + Hits 0 204 +204 - Misses 1141 2526 +1385 ```

:umbrella: View full report in Codecov by Sentry.
:loudspeaker: Have feedback on the report? Share it here.